The Work Limitations Questionnaire
Lerner, Debra MS, PhD*†; Amick, Benjamin C. III PhD‡; Rogers, William H. PhD*†; Malspeis, Susan SM§; Bungay, Kathleen PharmD*†; Cynn, Diane BA*
*From The Health Institute, Division of Clinical Care Research, New England Medical Center, Boston, Massachusetts. †From Tufts University School of Medicine, Boston, Massachusetts. ‡From the University of Texas Houston Health Sciences Center, School of Public Health, Houston, Texas, and the Institute for Work and Health, Toronto, Canada. §From Harvard School of Public Health, Boston, Massachusetts. Sponsored by Glaxo Wellcome, Inc.
Received December 6, 1999;
initial review completed February 22, 2000; accepted September 8, 2000.
Address correspondence and reprint requests to: Debra Lerner, MS, PhD, The Health Institute, New England Medical Center, NEMC Box 345, 750 Washington St, Boston, MA 02111. E-mail: firstname.lastname@example.org Address requests for the Work Limitations Questionnaire to: email@example.com
Objective. The objective of this work was to develop a psychometrically sound questionnaire for measuring the on-the-job impact of chronic health problems and/or treatment (“work limitations”).
Research Design. Three pilot studies (focus groups, cognitive interviews, and an alternate forms test) generated candidate items, dimensions, and response scales. Two field trials tested the psychometric performance of the questionnaire (studies 1 and 2). To test recall error, study 1 subjects were randomly assigned to 2 different questionnaire groups, a questionnaire with a 4-week reporting period completed once or a 2-week version completed twice. Responses were compared with data from concurrent work limitation diaries (the gold standard). To test construct validity, we compared questionnaire scores of patients with those of healthy job-matched control subjects. Study 2 was a cross-sectional mail survey testing scale reliability and construct validity.
Subjects. The study subjects were employed individuals (18–64 years of age) from several chronic condition groups (study 1, n = 48; study 2, n = 121) and, in study 1, 17 healthy matched control subjects.
Measures. Study 1 included the assigned questionnaires and weekly diaries. Study 2 included the new questionnaire, SF-36, and work productivity loss items.
Results. In study 1, questionnaire responses were consistent with diary data but were most highly correlated with the most recent week. Patients had significantly higher (worse) limitation scores than control subjects. In study 2, 4 scales from a 25-item questionnaire achieved Cronbach alphas of ≥0.90 and correlated with health status and self-reported work productivity in the hypothesized manner (P ≤0.05).
Conclusions. With 25 items, 4 dimensions (limitations handling time, physical, mental-interpersonal, and output demands), and a 2-week reporting period, the Work Limitations Questionnaire demonstrated high reliability and validity.
Approximately 55 million working-age individuals (18 to 65 years of age) have chronic illnesses and/or impairments and thus are vulnerable to disability. 1 Disabilities are a potential consequence of health problems and signify a partial or total inability to perform social roles in a manner consistent with norms or expectations. 2 National survey data suggest that 32% of employed adults have ongoing health problems that interfere with their ability to perform their job demands. 3 The national cost of lost work productivity resulting from chronic conditions has been estimated to be at least $234 billion annually. 4
Statistics such as these underlie a growing effort to document the social and economic outcomes of various chronic health problems and their treatment 5,6 and have spawned interest in including work disability and work productivity loss, defined collectively as “work loss,” as study end points. Because comprehensive archival work loss data are relatively scarce and difficult to obtain, research has relied principally on self-report. 7 Self-reports have addressed labor market participation, work absences, on-the-job effectiveness, and role disability. 8
Degree of labor market participation is a useful work loss indicator when a condition or treatment is expected to influence a person’s employment status and/or occupation. However, when these are infrequent outcomes, on-the-job performance measures have greater validity. One widely used indicator is the amount of time missed from work because of illness or treatment. 9,10 However, despite its acceptance, susceptibility to recall error remains a persistent concern. 11 Some studies have addressed on-the-job performance by asking individuals to rate their effectiveness on days when they are symptomatic, 12,13 although psychometric evidence is limited.
Scales such as the Role Limitation scales of the SF-36 represent another measurement approach using global, role-level disability indicators to capture disability in paid work and/or other activities (eg, “Were [you] limited in the kind of work or other activities?”). 14 However, disability scales can be relatively coarse, distinguishing a limited range of disability levels.
We developed the Work Limitations Questionnaire (WLQ) to fill this gap in measuring the on-the-job impact of chronic conditions and treatment. A long-term goal is to facilitate the economic assessment of work loss.
We report on 3 pilot studies and 2 psychometric field trials (studies 1 and 2). Appendix 1 describes each sample. Appendix 2 illustrates the genealogy of the WLQ items and scales.
The WLQ content and format originated from focus groups, cognitive interviews, and an alternate forms comparison. Each pilot included patients 18 to 64 years of age who were employed ≥20 h/wk within the following condition groups: respiratory diseases (asthma), gastrointestinal diseases (Crohn’s Disease and liver disease), psychiatric disorders (depression and/or generalized anxiety), or epilepsy (Appendix 1). We excluded patients with a planned or pending work disability claim and/or substance abuse problem. Participants received a monetary incentive ($40).
To identify questionnaire content, 4 condition-specific focus groups were convened. Four participating physicians were asked to nominate 5 to 10 patients. Twenty-one were nominated; 18 (86%) participated. Next, we created a list of discussion topics and a focus group guide. 15 Each topic addressed a job demand category contained within 2 well-known work classification taxonomies. 16,17 Each 2.5-hour discussion was audiotaped. Tapes were transcribed and analyzed.
Initially, each participant was asked to describe his/her job, health status, a “good” health day at work, and a “bad” day. Participants were also asked whether their jobs required them to perform each type of demand and how their health and medical care affected its performance. As a result, we generated 70 job demand–level limitation items and 7 dimensions (column 1, Appendix 2).
Cognitive interviews potentially enhance the reliability and validity of a questionnaire. 18,19 Using a think-aloud methodology, we assessed how another sample of respondents interpreted and answered the candidate items. The performance of each item was rated on the basis of interview data.
With a research assistant (RA) present, each of 37 respondents completed an open-ended questionnaire. The question asked: “In the past 4 weeks, how much difficulty did you have performing each of the following because of your physical health or emotional problems… ?” A list of job demands followed (eg, concentrating on work). This open-ended format meant that each respondent could choose a response terminology.
Respondents were instructed to read each question silently or aloud, paraphrase it, and think aloud while answering. A probing segment followed in which respondents discussed work limitations reported during the interview, misinterpreted or difficult items, and suggestions for additional topics. Interviews were audiotaped and coded.
Using the data, we rated items for their comprehensibility, redundancy, relevancy to job demands and health problems, and ease of responding. Items with high problem frequencies and/or relatively low work limitation rates were eliminated. As a result, 32 of 70 items failed. Of 38 passing items, 23 were revised to reduce awkward or unnecessary words. Two items were added (total of 40).
Several candidate items had validity problems. For example, certain items did not apply to respondents’ job demands. The Physical Demands section performed worst. This problem was cited in 23.6% of 407 administrations (37 subjects times 11 items). The corresponding rate for the best scale, Interpersonal Demands, was 3.2%. Other items lacked applicability to respondents’ illnesses. This deficiency was cited most frequently in response to items in the Information Processing section (17.6% of administrations). The Time Management section performed best in this regard (4.3% of administrations). Within each section, item redundancy problems occurred in 3% to 10% of administrations.
The Information Processing section had 1 passing item. It was included with Mental Demands. The Physical Environment items were deleted entirely because of interpretation problems. Thus, 40 items and 5 dimensions remained (Appendix 2).
No single response pattern emerged. Among the terms respondents used to answer questions were “difficult”/“not difficult,” “can do”/“can’t do,” “able to do”/“unable to do,” and “a problem”/“not a problem.”
In a third sample, we assessed the reliability of 3 different forms. Each contained the same 9 job demands embedded within the following stem/response options.
1. “In the past 4 weeks, how much difficulty have you had doing the following because of your physical health or emotional problems … ” (5 responses ranging from “no difficulty” to “so much difficulty I couldn’t do it”)? 2. “How much time during the past 4 weeks were you able to do the following … ” (5 responses ranging from “all of the time” to “none of the time”)? 3. “On how many days during the past 4 weeks were you able to do the following … ” (5 responses ranging from “more than 20 days” to ”0 days“)?
Each scale included the option “does not apply to my job.” The last 2 contained a follow-up yes/no item (“If able to do less than all of the time, was it due to your health?”).
We compared scales worded negatively (difficulty) and positively (able) and those measuring intensity (amount of difficulty) and frequency (amount of time). Questionnaires such as the SF-36 include intensity and frequency scales; however, the economic assessment of work loss usually involves a time factor (eg, lost work time). 10
The forms were completed in the presence of an RA. Order bias was reduced by shuffling forms before each administration.
During an audiotaped portion, participants were asked to describe their reasons for choosing certain responses, identify events that would have led to selecting another response, and rate the accuracy of responses.
The analysis compared responses on form 1 versus 2 versus 3. Matching responses were considered reliable. If responses did not match, we attempted to determine which was correct by comparing the mismatched responses with the transcripts.
Of the 324 responses compared (9 items times 36 subjects), 79% were 3-way matches, 20% were 2-way mismatches, and <1% were 3-way mismatches. Of the 2-way and 3-way mismatches, 68% involved a disagreement with the “days” form, and it was rejected (mismatch rates for the “difficulty” and “time able” forms rates were 32% and 38%, respectively).
We compared mismatched responses on the 2 remaining forms with transcript data and found that the “difficulty” form captured events more accurately than the “time able” form. Consequently, we adopted a difficulty question stem for 4 sections (Time, Mental, Interpersonal, and Output Demands). For Physical Demands, we adopted, “How much of the time were you able to do the following without difficulty due to physical health or emotional problems?” A single response scale was chosen—eg, all of the time (100%), a great deal of the time, some of the time (∼50%), a slight bit of the time, and none of the time (0%)—which could facilitate future economic analyses.
Field Trial Methods (Studies 1 and 2)
Using the 40 WLQ items and response scales developed in the pilot tests (Appendix 2), study 1 evaluated recall error. Two mail versions of the WLQ were tested: 1 with a 2-week reporting period and 1 with a 4-week reporting period. One randomly assigned group took the 2-week version, asking about work limitations in the past 2 weeks. It was administered at the end of study weeks 2 and 4. A different randomly assigned group took the 4-week version, asking about work limitations in the past 4 weeks. It was administered once at the end of study week 4. During the same weeks, both questionnaire groups also recorded work limitations on 4 weekly diaries (completed the last day of each week). These supplied a “gold standard” for judging the accuracy of the questionnaire data.
A case-control study was nested within study 1 comparing WLQ scores of patients and healthy coworkers matched on job and employer. Significantly higher (more limited) WLQ scores among patients provided initial evidence of construct validity.
Study 2 utilized a cross-sectional design to test 2 hypotheses: in H1, the WLQ contains internally consistent scales (a facet of reliability); in H2, scale scores correlate with measures of role disability and with self-reported work productivity (construct validity).
Study 1 included specialty clinic patients who met the pilot study criteria (Appendix 1). Site clinicians identified potentially eligible, interested patients. An RA called patients, explained the protocol, and assessed eligibility. Eligible study 1 patients were asked to nominate a job-matched coworker. Both were blinded to the fact that health status determined eligibility. To protect coworker confidentiality, each patient was asked to tell a coworker about the study and supply our phone number. During the call, the protocol was explained and eligibility was assessed. Eligible coworkers had the same job and employer as the patient, reported no major chronic conditions, and met the remaining study 1 criteria. Some patients, for privacy reasons, did not nominate a coworker or did not have a match. We included these patients in an “unmatched patient group” to participate in the questionnaire/diary protocol. All subjects received a monetary incentive to participate.
We attempted to recruit 60 subjects: 20 patient/coworker pairs (n = 40) and 20 unmatched patients; 90 patients were screened, and we enrolled 17 matched pairs (n = 34) and 31 unmatched patients (total n = 65; Appendix 1). The main reason for exclusion was lack of availability for 4 consecutive weeks. Additionally, we reduced the number of matched pairs from 17 to 14 after 3 “healthy” controls were found to have SF-36 mental health scores indicative of clinical depression. 20
Each subject was randomized to a questionnaire group (with matched pairs assigned to the same group). We assigned 29 subjects (45%) to the 2-week WLQ group and 36 (55%) to the 4-week group. Using χ2 or t test statistics as appropriate, we found no significant differences between the questionnaire groups on mean age, percent male, mean education, occupation (percent manual versus nonmanual), 21 percent with a condition, and mean SF-36 scale scores.
Study 2 consisted of 3 groups: (1) rheumatoid arthritis patients from specialty clinics (A), (2) chronic daily headache syndrome patients from one clinic (H), and (3) an epilepsy group from the membership of 2 epilepsy foundations (E). Site investigators identified potentially eligible A and H subjects. E subjects received announcements in foundation newsletters. Interested individuals in all groups were asked to call a toll-free phone number.
Study 2 applied the study 1 condition criteria and a monetary incentive. Additionally, A subjects had moderate to severe functional limitations according to phone responses to the SF-36 Physical Functioning scale (ie, ≥2 “limited a little” responses, or 1 “limited a lot” response). E subjects reported ≥1 seizure in the past year. H subjects had clinic-documented impairments (eg, sleep disturbance). Of 188 screened, 133 enrolled. The final sample size was 121 (nonresponse=12; 9%).
Study 1 and 2 subjects completed a background questionnaire assessing employment, health status, 14 comorbidities, 22 condition-specific and generic symptoms, 22,23 and demographics.
Additionally, study 1 subjects were required to complete their assigned WLQs (2-week or 4-week) and 4 weekly mail-out/mail-back diaries. Materials were mailed simultaneously for matched subjects.
To minimize the threat of repeated administration bias from completing diaries and questionnaires, we divided the 40-item pool among the 2 forms. Each form contained 5 WLQ dimensions with ≥2 items per dimension. We tried to equalize item content across forms, giving the diaries 18 items and the questionnaires 22 items (column 2, Appendix 2).
The study 2 sample completed a mail-out/mail-back WLQ (with a 2-week reporting period) containing the same 5 dimensions and 40 items, as well as 8 items suggested by the research team (column 3, Appendix 2). We also measured work absences and work hours, job effectiveness on symptom days (“0% not at all effective” through “100% completely effective”), and 2 work productivity items (“In the past 2 weeks, did you produce less than the required amount of products or services,” and “did you produce less than the required quality of products or services?” “If yes, was this due to your health?”). Late responders received a call and/or second mailing.
Before performing the main analyses, we determined whether the 5 hypothesized WLQ scales met scaling assumptions established by classical test theory. MAP-R software was used. 24 Results suggested that 4 scales were present: Time, Physical, Mental-Interpersonal, and Output Demands. Scale Cronbach alphas 25 ranged from 0.90 (κ = 7) to 0.96 (k = 11).
Next, a scoring algorithm was created especially for these tests, incorporating both WLQ and diary data: (1) Scores for items administered weekly or biweekly were averaged across administration weeks; (2) the resultant average scores for items within a scale were summed, and the sum was divided by the total number of scale items (the summated average scale score ranged from 0–4); and (3) scores were multiplied by 25, generating a scale score of 0 (least limited) to 100 (most limited). “Does not apply to my job” responses were treated as missing. Thus, an Output Demands scale score of 30, for example, indicated that the respondent was limited in performing these demands during 30% of the reporting period.
Two-Week Versus Four-Week Recall.
Both the 2-week and 4-week versions of the WLQ were assessed with regard to recall error. In 8 models (4 scales times 2 WLQ versions), the dependent variable was a scale score to which each subject contributed 2 data points: 1 score reflecting aggregated weekly diary data, and a corresponding score utilizing questionnaire data. The explanatory variables were indicators for “subject” and “method” (diary versus questionnaire).
F statistics and probability values generated by 2-way analysis of variance (ANOVA) indicated the significance of subject and/or method in explaining WLQ scores. An intraclass correlation coefficient (ICC) ≥0.70 indicated acceptable scale performance. 26
Bias by Week.
This second recall error test addressed the degree to which WLQ responses reflected limitations from all weeks within the specified reporting period. Ideally, responses should include information equally from all weeks.
With multiple linear regression, the dependent variable of each model was a WLQ scale score from a specific questionnaire administration (the first administration of the 2-week version, the second administration of the 2-week version, or the single administration of the 4-week version). The independent variables were work limitation scale scores reported on parallel diary weeks (eg, weeks 1–2 for the first administration of the 2-week WLQ, weeks 1–4 for the 4-week WLQ).
Regressions compared the relative influence of each week within the reporting period. Because results indicated that WLQ scores were explained mainly by events from the most recent week, subsequent regressions tested the importance of the most recent diary week versus the mean of all diary weeks in the reporting period (ie, whether scores reflected recent events and/or the average across weeks). Twenty-four models were tested (3 WLQs times 4 scales times 2 comparisons).
To test construct validity, the mean difference in each WLQ scale score between matched patient-coworker pairs was analyzed with paired t tests.
Using MAP-R, the following characteristics of the 48-item WLQ were evaluated: (1) scale means, SDs, and floor (minimum) and ceiling (maximum) effects; (2) item-to-total scale correlations corrected for overlap; (3) Cronbach’s alphas for internal consistency reliability; and (4) scaling success rates (percent of tests out of all possible tests in which the correlation of an item with its hypothesized scale is ≥2 standard errors higher than its correlation with other scales). Success rates ≥90% are considered excellent. Scale scores were the means of item responses within each scale multiplied by 25.
Next, we attempted to create a shorter WLQ without sacrificing content, validity, and reliability. From the 48-item pool, 25 were chosen and tested (column 3, Appendix 2). They were selected for 3 reasons: excellent MAP-R results, significant correlation with productivity variables, and unduplicated content.
In separate multiple linear regression models adjusted for age and gender, we tested the relationship of each WLQ scale score to the SF-36 Role/Physical scale (limitations resulting from physical health) and Role/Emotional scale (limitations resulting from emotional problems). We also assessed whether WLQ scores varied by condition (A, H, and E) using age- and gender-adjusted ANOVA.
The association between each WLQ scale to self-reported work productivity (the sum of responses to the 2 productivity items) was compared with those of the following measures: percent of time absent because of health, effectiveness on symptom days (both for the past 2 weeks), and the SF-36 Role Limitation scales. Relative validity was quantified as a ratio of F statistics obtained from multiple linear regression. The numerator was the F statistic obtained from regressing work productivity on a specific scale. The denominator was the F value for the best scale in the comparison (maximum ratio = 1).
Two-Week Versus Four-Week Recall.
Performance on this recall error test varied by scale and version (Table 1). The Time and Mental-Interpersonal Demands scales (2-week and 4-week versions) both exceeded the ICC criterion. The Physical and Output Demands scales, 4-week version, met the criterion, but method contributed in several models. Method had a small impact compared with subject. Initially, the ICC standard was not met by the Physical or Output Demands scales 2-week version (Physical = 0.64; Output = 0.58). However, 2 subjects with logically inconsistent data were excluded, and the criterion was met (Physical = 0.69; Output = 0.74).
Bias by Week.
In 12 models assessing the degree to which data from individual weeks predicted WLQ scores, the most recent week tended to have the most influence (Table 2). When the most recent week was compared with the mean of the weeks, both variables were important. In 3 models, only the mean was significant (P ≤0.05); in 2 models, only the most recent week was significant; and in 2 models, both were significant. In 5 of the 2-week version models, neither variable was significant. Thus, subjects tended to respond by reporting the average amount of the time they were limited during the reporting period and/or those limitations that occurred most recently. While results suggest that it is better to use a shorter reporting period such as a 2-week interval, the 4-week version also performed satisfactorily.
On each WLQ scale, patients had significantly higher (worse) work limitation scores than control subjects (Figure 1). The unmatched patient group had the highest WLQ scores, indicating the most limitation of the groups.
On the 48-item WLQ, the percentages for “limited none of the time,” “a slight bit of the time,” “some of the time,” “most of the time,” and “all of the time” were 47.8%, 30.8%, 10.6%, 6.8%, and 3.8%, respectively. The frequency of “does not apply to my job” responses was small (range, 0–5 subjects per item).
The analysis confirmed 5 scales (Table 3). With a small number of exceptions, the correlation of each item to its hypothesized scale was ≥2 standard errors higher than its correlation with other scales, item-to-total scale correlation coefficients surpassed 0.40, and alphas were ≥0.90.
When the 25-item subset was assessed, the percentage of Interpersonal scale responses at the floor (zero) increased unacceptably. We tested whether its items could be combined with the Mental Demands scale. MAP-R results supported a 4-scale solution: Time, Physical, Mental-Interpersonal, and Output Demands (Table 3).
In separate regression models, each WLQ scale explained a significant portion of the variance in the SF-36 Role/Physical scale, and 3 WLQ scales explained a significant amount of the variation in the SF-36 Role/Emotional scale (Table 4). The WLQ Physical Demands scale was appropriately unrelated to emotional disability.
WLQ scores varied significantly by condition (Figure 2). Additionally, within each scale, the pattern of limitation was logically consistent with the characteristics of the different conditions. For example, headache syndrome involves sleep disturbance, fatigue, and extreme pain, which disrupt activities. H was the more limited than A (P = 0.02) or E (P <0.001) on the Time Demands scale. Headaches also involve visual and neurologic disturbances, depressed affect, and irritability. Compared with either A or E, H was most limited on the Mental-Interpersonal Demands scale (both P <0.01). On the Physical Demands scale, A was more limited than H (P <0.001) or E (P = 0.03).
The WLQ Output Demands scale was the best predictor of productivity loss (Figure 3). The WLQ Mental-Interpersonal Demands and the SF-36 Role Limitation scales each exhibited half the predictive power of the Output Demands scale. The remaining measures had poorer predictive power.
The WLQ is a reliable and valid self-report instrument for measuring the degree to which chronic health problems interfere with ability to perform job roles. Unlike available questionnaires, it addresses the content of the job through a demand-level methodology.
The WLQ performed well in studies 1 and 2. The study 1 diary/questionnaire comparison, while small and involving multiple comparisons, demonstrated that compared with diary data, both the 2-week and 4-week WLQs were relatively unbiased. However, the questionnaire responses were related more strongly to the most recent week of the reporting period than to earlier weeks. The ease of remembering recent events may reflect the difficulty of the response task. Respondents must remember and integrate information about their health and work simultaneously. We recommend the 2-week WLQ to maximize accuracy. However, if it is important to match time periods across instruments within a study, the 4-week version is acceptable. In such situations, a single administration of the 4-week WLQ would achieve better precision than a single administration of the 2-week WLQ, and cost less than multiple administrations of the shorter version.
Study 2 indicated that the 25-item WLQ was reliable and valid for use among several different job and chronic condition groups. However, our sample included only adults working ≥20 h/wk, possibly excluding employed individuals with severe work limitations, and only certain diagnostic groups. The 25-item WLQ has been evaluated in additional patient and employee samples, and it has demonstrated excellent performance (data available from authors).
The analyses also confirmed 4 distinct dimensions of on-the-job disability (limitations handling Time, Physical, Mental-Interpersonal, and Output Demands). The multidimensionality of the WLQ is likely to appeal to clinicians, other disability management professionals, and employers. Because the WLQ is context specific and focused on job demand performance, it can be used to identify both the magnitude and type of impact that health problems are having in the workplace. In contrast, role disability scales are pitched at too high a level of generality to be of practical value. Moreover, construct validity test results indicated that the WLQ Output Demands scale had superior performance for predicting productivity. The Mental-Interpersonal Demands and the SF-36 Role Limitation scales had moderate validity. Thus, the WLQ provides more specific information than available instruments while increasing the depth and breadth of information generated. However, there is a trend in health status assessment toward using summary scores, and future WLQ users may prefer a similar approach.
While this project involved multiple psychometric assessments, our tests stopped short of addressing certain issues. We did not attempt to measure abilities that exceed demands, the positive end of the ability spectrum. We did not assess test-retest reliability and responsiveness to change within condition groups. The value of the WLQ as a productivity indicator was addressed briefly; criterion validity tests linking scores to objective work output were not performed. We did not explore how job demand variations may impact WLQ data. Finally, we did not fully assess our scoring method, which combines within-scale limitations by averaging them. Ideally, a scale would capture the intensity of each limitation measured and its frequency; however, this may result in a cumbersome instrument.
Study results provide important evidence of the reliability and validity of the WLQ. It is a promising new tool for assessing chronic health problems and their social and economic impact.
We wish to acknowledge Glaxo Wellcome, Inc, Research Triangle Park, North Carolina, for its sponsorship of the research project and the Henry J. Kaiser Family Foundation of Palo Alto, California. We also wish to express our gratitude to the following site investigators: Leonard Sicilian, MD, Bruce Ehrenberg, MD, David Adler, MD, Peter Bonis, MD, Anne Marie Brown, BS, RN, Laurie Olans, MD, and Arthur A. Wills III, MD, all from the New England Medical Center; Saralynn Allaire, ScD, of the Boston University School Of Medicine Multi-Purpose Arthritis Center; and Lawrence C. Newman, MD, and Margie Russell, RN, of the Montefiore Hospital Headache Clinic. Additionally, we wish to extend our appreciation to Anita Wagner, PharmD, and Constance Kelley for their invaluable participation and advice throughout the study. Patients in this study were recruited from the New England Medical Center (Respiratory, Gastroenterology, Psychiatry, and Neurology departments), Downtown Medical Associates (a New England Medical Center affiliate), Boston University, The Epilepsy Foundation of Massachusetts and Rhode Island, the Epilepsy Foundation of Connecticut, and the former Massachusetts Respiratory Hospital in Weymouth, Massachusetts. We gratefully acknowledge the participation of each.
TABLE 5 of Appendix 1 gives the sample characteristics. Cited Here...
TABLE 6 Cited Here...
1. Kaye HS, LaPlante MP, Carlson D, et al. Trends in disability rates in the United States, 1970–1994. Disabil Stats Abstract 1996; 17: 1–6.
2. Pope A, Tarlov AR. Disability in America: Toward a national agenda for prevention. Washington, DC: Division of Health Promotion and Disease Prevention, Institute of Medicine, National Academy Press; 1991.
3. Lerner DJ, Amick BC III, Malspeis S, et al. A national survey of health-related work limitations among employed persons in the United States. Disabil Rehabil 2000; 22: 225–232.
4. Hoffman C, Rice D, Sung HY. Persons with chronic conditions: Their prevalence and costs. JAMA 1996; 276: 1473–1479.
5. Freudenheim E, ed. Chronic care in America: A 21st century challenge. Princeton, NJ: Robert Wood Johnson Foundation; 1996.
6. National Institute for Occupational Safety and Health. National occupational research agenda. Cincinnati, Ohio: US Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health; 1996. DHHS publication No. 96-115.
7. Lerner D, Lee J. Measuring health-related work productivity with self-reports. In: Stang P, Kessler RC, eds. Health and work productivity: Emerging issues in research and policy. Chicago, Ill: University of Chicago Press. In press.
8. Lerner DJ, Bungay KM. Measuring work outcomes. In: Pharmacoeconomics and outcomes: Applications for patient care, module 3: Assessment of humanistic outcomes. Kansas City, Mo: American College of Clinical Pharmacy; 1997:171–185.
9. Ormel J, Von Korff M, Oldehinkel AJ, et al. Onset of disability in depressed and non-depressed primary care patients. Psychol Med 1999; 29: 847–853.
10. Greenberg PE, Stiglin LE, Finkelstein SN, et al. The economic burden of depression in 1990. J Clin Psychiatry 1993; 54: 405–418.
11. Johns G. Absenteeism estimates by employees and managers: Divergent perspectives and self-serving perceptions. J Appl Psychol 1994; 79: 229–239.
12. Osterhaus JT, Gutterman DL, Plachetka JR. Healthcare resource and lost labor costs of migraine headache in the US. Pharmacoeconomics 1992; 2: 67–76.
13. Reilly MC, Zbrozek AS, Dukes EM. The validity and reproducibility of a work productivity and activity impairment instrument. Pharmacoeconomics 1993; 4: 353–365.
14. Ware JE, Snow KK, Kosinski M, et al. SF-36 Health Survey: Manual and interpretation guide. Boston, Mass: Health Institute, New England Medical Center; 1993.
15. Krueger RA. Group dynamics and focus groups. In: Spilker B, ed. Quality of life and pharmacoeconomics in clinical trials. 2nd ed. Philadelphia, Pa: Lippincott-Raven; 1996: 397–402.
16. Employment and Training Administration, US Employment Service. Dictionary of occupational titles. 4th ed. Washington, DC: US Department of Labor; 1991.
17. McCormick EJ, Jeanneret PR, Mecham RC. The Position Analysis Questionnaire (PAQ). Palo Alto, Calif: Consulting Psychologists Press Inc; 1989.
18. Sudman S, Bradburn NM, Schwarz N. Thinking about answers: The application of cognitive processes to survey methodology. San Francisco, Calif: Jossey-Bass Publishers; 1996.
19. Streiner DL, Norman GR. Health measurement scales: A practical guide to their development and use. 2nd ed. New York, NY: Oxford University Press; 1995.
20. Berwick D, Murphy J, Goldman P, et al. Performance of a five-item mental health screening test. Med Care 1991; 29: 169–176.
21. US Department of Commerce. Classified index of industries and occupations. Washington, DC: US Government Printing Office; 1992.
22. Stewart A, Ware JE Jr, eds. Measuring functioning and well-being. Durham, NC: Duke University Press; 1992.
23. Baker GA, Smith DF, Dewey M, et al. The development of a seizure severity scale as an outcome measure in epilepsy. Epilepsy Res 1991; 8: 245–251.
24. Ware JE, Harris WJ, Gandek B, et al. MAP-R for Windows: Multitrait/multi-item analysis program. Boston, Mass: Health Assessment Lab; 1997. Computer program.
25. Cronbach LJ. Essentials of psychological testing. 4th ed. New York, NY: Harper and Row; 1984.
26. Shrout PE, Fleiss JL. Intraclass correlations: Uses in assessing rater reliability. Psychol Bull 1979; 86: 40.
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Disability and RehabilitationWorkers with health problems: three perspectives on functioning at workDisability and Rehabilitation
Value in HealthThe Use and Performance of Productivity Scales to Evaluate Presenteeism in Mood DisordersValue in Health
Disability and RehabilitationWork-related self-report measures and assessment tools in cancer survivorship: A systematic literature reviewDisability and Rehabilitation
Research in Nursing & HealthSleep loss and its effects on health of family caregivers of individuals with primary malignant brain tumorsResearch in Nursing & Health
Arthritis Care & ResearchTreating to a Target in Established Active Rheumatoid Arthritis Patients Receiving a Tumor Necrosis Factor Inhibitor: Results From a Real-World Cluster-Randomized Adalimumab TrialArthritis Care & Research
American Journal of Health PromotionHealthy Workplaces? A Survey of Massachusetts EmployersAmerican Journal of Health Promotion
Journal of Cancer Survivorship-Research and PracticeBrief self-report measure of work-related cognitive limitations in breast cancer survivorsJournal of Cancer Survivorship-Research and Practice
Bmc PsychiatryA decision aid to assist decisions on disclosure of mental health status to an employer: protocol for the CORAL exploratory randomised controlled trialBmc Psychiatry
Journal of Rehabilitation Research and DevelopmentMental health assessment in rehabilitation researchJournal of Rehabilitation Research and Development
Journal of Rehabilitation Research and DevelopmentAssessment of posttraumatic stress disorder-related functional impairment: A reviewJournal of Rehabilitation Research and Development
Developmental Medicine and Child NeurologyA new intervention to improve work participation of young adults with physical disabilities: a feasibility studyDevelopmental Medicine and Child Neurology
Work-A Journal of Prevention Assessment & RehabilitationWork limitations, workplace concerns, and job satisfaction of persons with chronic diseaseWork-A Journal of Prevention Assessment & Rehabilitation
Athletic Therapy Today
The imput of health problems affecting worker productivity in a manufacturing setting
Athletic Therapy Today, 8(3):
Alimentary Pharmacology & TherapeuticsSystematic review: the impact of gastro-oesophageal reflux disease on work productivityAlimentary Pharmacology & Therapeutics
Living in A Chemical World: Framing the Future in Light of the PastOccupational injury and illness meet the labor market - Lessons from labor economics about lost earningsLiving in A Chemical World: Framing the Future in Light of the Past
Journal of Occupational RehabilitationWork factors related to psychological and health-related distress among employees with chronic illnessesJournal of Occupational Rehabilitation
Clinical RheumatologySick leave and work disability in patients with early arthritisClinical Rheumatology
Journal of Occupational RehabilitationComparison of the Psychometric Properties of Four At-Work Disability Measures in Workers with Shoulder or Elbow DisordersJournal of Occupational Rehabilitation
Design characteristics of worksite environmental interventions for obesity prevention
Clinical and Experimental Rheumatology
A mismatch between self-reported physical work load and the HAQ: early identification of rheumatoid arthritis patients at risk for loss of work productivity
Clinical and Experimental Rheumatology, 27(3):
Journal of RheumatologyMeasuring Worker Productivity: Frameworks and MeasuresJournal of Rheumatology
Bmc PsychiatryA new clinical rating scale for work absence and productivity: validation in patients with major depressive disorderBmc Psychiatry
The effect of improving primary care depression management on employee absenteeism and productivity - A randomized trial
Medical Care, 42():
Journal of Rheumatology
Physical function and health related quality of life: Analysis of 2-year data from randomized, controlled studies of leflunomide, sulfasalazine, or methotrexate in patients with active rheumatoid arthritis
Journal of Rheumatology, 32(4):
Quality of Life ResearchBeyond return to work: Testing a measure of at-work disability in workers with musculoskeletal painQuality of Life Research
Journal of Bone and Joint Surgery-American VolumeLumbar disc disorders and low-back pain: Socioeconomic factors and consequencesJournal of Bone and Joint Surgery-American Volume
American Journal of Health Promotion
The association of two productivity measures with health risks and medical conditions in an Australian employee population
American Journal of Health Promotion, 20(5):
Journal of Occupational RehabilitationAssociation of low back pain, impairment, disability & work limitations in nursesJournal of Occupational Rehabilitation
European Journal of Physical and Rehabilitation Medicine
A comparison of functional assessment instruments and work status in chronic back pain
European Journal of Physical and Rehabilitation Medicine, 45(1):
RheumatologyThe effect of etanercept on work productivity in patients with early active rheumatoid arthritis: results from the COMET studyRheumatology
Journal of Mental Health Policy and Economics
Economic Outcomes of Eszopiclone Treatment in Insomnia and Comorbid Major Depressive Disorder
Journal of Mental Health Policy and Economics, 13(1):
Clinical Orthopaedics and Related ResearchMeasures of health-related quality of life and physical functionClinical Orthopaedics and Related Research
Quality of Life Research
Applications of computerized adaptive testing (CAT) to the assessment of headache impact
Quality of Life Research, 12(8):
A review of self-report instruments measuring health-related work productivity - A patient-reported outcomes perspective
Patient Education and CounselingWhat employees with diabetes mellitus need to cope at work: Views of employees and health professionalsPatient Education and Counseling
Asia Pacific Journal of Clinical Nutrition
An integrated intervention program to control diabetes in overweight Chinese women and men with type 2 diabetes
Asia Pacific Journal of Clinical Nutrition, 17(3):
Journal of Occupational and Environmental MedicineCaregiving for ill dependents and its association with employee health risks and productivityJournal of Occupational and Environmental Medicine
Nightly treatment of primary insomnia with eszopiclone for six months: Effect on sleep, quality of life, and work limitations
Journal of Occupational RehabilitationEmployee health and presenteeism: A systematic reviewJournal of Occupational Rehabilitation
Current Medical Research and OpinionHealth-related quality of life (HRQOL) among patients with Generalised Anxiety Disorder: evaluation conducted alongside an escitalopram relapse prevention trialCurrent Medical Research and Opinion
Journal of Rheumatology
Work limitations among working persons with rheumatoid arthritis: Results, reliability, and validity of the work limitations questionnaire in 836 patients
Journal of Rheumatology, 32(6):
American Journal of Industrial Medicine
Quantifying social consequences of occupational injuries and illnesses: State of the art and research agenda
American Journal of Industrial Medicine, 40(4):
Geneva Papers on Risk and Insurance-Issues and Practice
Ageing, disability and the WHO's international classification of functioning, disability and health (ICF)
Geneva Papers on Risk and Insurance-Issues and Practice, 28(2):
A review of health-related workplace productivity loss instruments
Journal of Clinical EpidemiologyHealth problems lead to considerable productivity loss at work among workers with high physical load jobsJournal of Clinical Epidemiology
Journal of Occupational RehabilitationIncorporating injured employee outcomes into physical and occupational therapists' practice: A controlled trial of the worker-based outcomes assessment systemJournal of Occupational Rehabilitation
American Journal of Health Promotion
Work Performance of Employees With Depression: The Impact of Work Stressors
American Journal of Health Promotion, 24(3):
Arthritis & Rheumatism-Arthritis Care & ResearchDevelopment of a work instability scale for rheumatoid arthritisArthritis & Rheumatism-Arthritis Care & Research
Arthritis and RheumatismDirect medical costs and their predictors in patients with rheumatoid arthritis - A three-year study of 7,527 patientsArthritis and Rheumatism
Journal of Occupational and Environmental MedicineA validity analysis of the work productivity short inventory (WPSI) instrument measuring employee health and productivityJournal of Occupational and Environmental Medicine
Alimentary Pharmacology & TherapeuticsThe validity and accuracy of the Work Productivity and Activity Impairment questionnaire - irritable bowel syndrome version (WPAI : IBS)Alimentary Pharmacology & Therapeutics
Measuring productivity changes in economic evaluation - Setting the research agenda
Validation of the Dutch Occupational Impact of Sleep Questionnaire (OISQ)
Industrial Health, 46(6):
Cost-Effectiveness of Eszopiclone for the Treatment of Adults with Primary Chronic Insomnia
Arthritis Research & TherapyDiscriminant validity, responsiveness and reliability of the rheumatoid arthritis-specific Work Productivity Survey (WPS-RA)Arthritis Research & Therapy
American Journal of Managed Care
A review of methods to measure health-related productivy loss
American Journal of Managed Care, 13(4):
Journal of Occupational RehabilitationPsychometric evaluation of health-related work outcome measures for musculoskeletal disorders: A systematic reviewJournal of Occupational Rehabilitation
Occupational Medicine-OxfordUse of prescribed medication at work in employees with chronic illnessOccupational Medicine-Oxford
Arthritis & Rheumatism-Arthritis Care & ResearchWork disability and its economic effect on 55-64-year-old adults with rheumatoid arthritisArthritis & Rheumatism-Arthritis Care & Research
Journal of Rheumatology
Household income and earnings losses among 6,396 persons with rheumatoid arthritis
Journal of Rheumatology, 32():
International Archives of Occupational and Environmental HealthSick leave as a predictor of job loss in patients with chronic arthritisInternational Archives of Occupational and Environmental Health
Disability and RehabilitationEffectiveness of workplace rehabilitation interventions in the treatment of work-related low back pain: A systematic reviewDisability and Rehabilitation
Zolpidem extended-release 12.5 mg associated with improvements in work performance in a 6-month randomized, placebo-controlled trial
Arthritis & Rheumatism-Arthritis Care & ResearchA Proof-of-Concept Study of the "Employment and Arthritis: Making it Work" ProgramArthritis & Rheumatism-Arthritis Care & Research
Bju InternationalThe prevalence of lower urinary tract symptoms (LUTS) in the USA, the UK and Sweden: results from the Epidemiology of LUTS (EpiLUTS) studyBju International
Clinical and Experimental Rheumatology
Assessment of work disability in seronegative spondyloarthropathy (SpA)
Clinical and Experimental Rheumatology, 28(1):
Disability and RehabilitationFactors contributing to work-ability for injured workers: literature review and comparison with available measuresDisability and Rehabilitation
Journal of Advanced Nursing
Cognitive interviewing: verbal data in the design and pretesting of questionnaires
Journal of Advanced Nursing, 42(1):
Journal of Orthopaedic & Sports Physical Therapy
Guide to outcomes measurement for patients with low back pain syndromes
Journal of Orthopaedic & Sports Physical Therapy, 33(6):
Journal of Occupational Rehabilitation
Functional limitations and well-being in injured municipal workers: A longitudinal study
Journal of Occupational Rehabilitation, 14(2):
Arthritis & Rheumatism-Arthritis Care & ResearchRandomized comparison of a multidisciplinary job-retention vocational rehabilitation program with usual outpatient care in patients with chronic arthritis at risk for job lossArthritis & Rheumatism-Arthritis Care & Research
American Journal of Psychiatry
Job performance deficits due to depression
American Journal of Psychiatry, 163(9):
American Journal of Industrial MedicineEvaluation of a participatory ergonomic intervention aimed at improving musculoskeletal healthAmerican Journal of Industrial Medicine
Journal of Rheumatology
Worker productivity outcome measures in arthritis
Journal of Rheumatology, 34(6):
Quality of Life ResearchHealth status, work limitations, and return-to-work trajectories in injured workers with musculoskeletal disordersQuality of Life Research
Best Practice & Research in Clinical RheumatologyRehabilitation in musculoskeletal diseasesBest Practice & Research in Clinical Rheumatology
Impact of Transdermal Oxybutynin on Work Productivity in Patients with Overactive Bladder Results from the MATRIX Study
American Journal of Health Promotion
Factors Associated With Incidental Sickness Absence Among Employees in One Health Care System
American Journal of Health Promotion, 24(1):
Current Medical Research and OpinionInterpreting score differences in the Insomnia Severity Index: using health-related outcomes to define the minimally important differenceCurrent Medical Research and Opinion
Migraine headache misconceptions: Barriers to effective care
Work-related outcomes after a myocardial infarction
American Journal of Managed Care
Impairment in work productivity and health-related quality of life in patients with IBS
American Journal of Managed Care, 11(1):
International Journal of Psychiatry in MedicineEffectiveness of A Depression Disease Management Program in Improving Depression and Work Function-A Pilot StudyInternational Journal of Psychiatry in Medicine
American Journal of Health Promotion
Best Practices in Evaluating Worksite Health Promotion Programs
American Journal of Health Promotion, 24(3):
Journal of Organizational BehaviorPresenteeism in the workplace: A review and research agendaJournal of Organizational Behavior
Journal of Clinical Epidemiology
The Work Limitations Questionnaire's validity and reliability among patients with osteoarthritis
Journal of Clinical Epidemiology, 55(2):
Journal of Occupational RehabilitationReturn-to-work outcomes following work disability: Stakeholder motivations, interests and concernsJournal of Occupational Rehabilitation
Disease Management & Health Outcomes
Worksite disease management programs for depression - Potential employer benefits
Disease Management & Health Outcomes, 14(1):
Clinical TherapeuticsA disease-specific measure of health-related quality of life in adults with chronic immune thrombocytopenic purpura: Psychometric testing in an open-label clinical trialClinical Therapeutics
Work-A Journal of Prevention Assessment & Rehabilitation
Age, work limitations and physical functioning among construction roofers
Work-A Journal of Prevention Assessment & Rehabilitation, 31(4):
Seminars in Arthritis and RheumatismAssessing the Impact of Psoriatic Arthritis on Patient Function and Quality of Life: Lessons Learned from Other Rheumatologic ConditionsSeminars in Arthritis and Rheumatism
Scandinavian Journal of Work Environment & Health
Methodological issues in evaluating workplace interventions to reduce work-related musculoskeletal disorders through mechanical exposure reduction
Scandinavian Journal of Work Environment & Health, 29(5):
Bmc Musculoskeletal DisordersAll-arthroscopic versus mini-open repair of small or moderate-sized rotator cuff tears: A protocol for a randomized trialBmc Musculoskeletal Disorders
Revista Panamericana De Salud Publica-Pan American Journal of Public Health
Translation into Brazilian Portuguese and validation of the work limitations questionnaire
Revista Panamericana De Salud Publica-Pan American Journal of Public Health, 22(1):
Preventive MedicineMeasuring the effect of workplace health promotion interventions on "presenteeism": A potential role for biomarkersPreventive Medicine
Depression and AnxietySeverity of Anxiety and Work-Related Outcomes of Patients With Anxiety DisordersDepression and Anxiety
Sleep Medicine ReviewsInsomnia and health-related quality of lifeSleep Medicine Reviews
Bmc Public HealthWorksite interventions for preventing physical deterioration among employees in job-groups with high physical work demands: Background, design and conceptual model of FINALEBmc Public Health
CancerAssessing the impact of cancer on work outcomes - What are the research needs?Cancer
Journal of Rheumatology
Arthritis and employment research: Where are we? Where do we need to go?
Journal of Rheumatology, 32():
Value in Health
Indirect costs of respiratory syncytial virus hospitalizations: A commentary
Value in Health, 6(2):
Arthritis & Rheumatism-Arthritis Care & ResearchLongitudinal study of negative workplace events among employed rheumatoid arthritis patients and healthy controlsArthritis & Rheumatism-Arthritis Care & Research
GastroenterologyA randomized, double-blind, sham-controlled study of granulocyte/monocyte apheresis for active ulcerative colitisGastroenterology
Clinical Psychology ReviewThe importance of functional impairment to mental health outcomes: A case for reassessing our goals in depression treatment researchClinical Psychology Review
Alimentary Pharmacology & TherapeuticsThe burden of illness of gastro-oesophageal reflux disease: impact on work productivityAlimentary Pharmacology & Therapeutics
Scandinavian Journal of Work Environment & Health
Musculoskeletal disorders among construction roofers-physical function and disability
Scandinavian Journal of Work Environment & Health, 35(1):
American Journal of Industrial MedicineStress and work-related upper extremity disorders: Implications for prevention and managementAmerican Journal of Industrial Medicine
General Hospital PsychiatryThe work impact of dysthymia in a primary care populationGeneral Hospital Psychiatry
Current Medical Research and OpinionEconomic impact of workplace productivity losses due to allergic rhinitis compared with select medical conditions in the United States from an employer perspectiveCurrent Medical Research and Opinion
Occupational Medicine-OxfordThe work limitation questionnaireOccupational Medicine-Oxford
The Cost and Impact of Health Conditions on Presenteeism to Employers A Review of the Literature
Journal of Occupational RehabilitationContent Comparison of Worker Productivity Questionnaires in Arthritis and Musculoskeletal Conditions Using the International Classification of Functioning, Disability, and Health FrameworkJournal of Occupational Rehabilitation
American Journal of Health Promotion
The association of corporate work environment factors, health risks, and medical conditions with presenteeism among Australian employees
American Journal of Health Promotion, 21(2):
Work-A Journal of Prevention Assessment & Rehabilitation
Evaluation of selected ergonomic assessment tools for use in providing job accommodation for people with inflammatory arthritis
Work-A Journal of Prevention Assessment & Rehabilitation, 31(2):
RheumatologyValidation of a simple activity participation measure for rheumatoid arthritis clinical trialsRheumatology
Journal of Hand Surgery-American VolumeFunctional Outcome of Arthroscopic Extensor Carpi Radialis Brevis Tendon Release in Chronic Lateral EpicondylitisJournal of Hand Surgery-American Volume
Journal of Traumatic StressWork Limitations in Employed Persons Seeking Treatment for Chronic Posttraumatic Stress DisorderJournal of Traumatic Stress
American Journal of Industrial MedicineImpact of Musculoskeletal and Medical Conditions on Disability Retirement-A Longitudinal Study Among Construction RoofersAmerican Journal of Industrial Medicine
Unemployment, job retention, and productivity loss among employees with depression
Psychiatric Services, 55():
DermatologyWork limitations and productivity loss are associated with health-related quality of life but not with clinical severity in patients with psoriasisDermatology
Sleep MedicineInsomnia and its relationship to health-care utilization, work absenteeism, productivity and accidentsSleep Medicine
Journal of Clinical EpidemiologyDisability in depression and back pain - Evaluation of the World Health Organization Disability Assessment Schedule (WHO DAS II) in a primary care settingJournal of Clinical Epidemiology
Journal of Occupational Health PsychologyChildren's health and workers' productivity: An examination of family interference with work in rural AmericaJournal of Occupational Health Psychology
Depression and Anxiety
Patient-reported health-related work productivity in panic desorder: Venlafaxine, paroxetine, and placebo
Depression and Anxiety, 22(4):
Cochrane Database of Systematic ReviewsInterventions to facilitate return to work in adults with adjustment disordersCochrane Database of Systematic Reviews
Revista Brasileira De Reumatologia
Variables related to work productivity loss in patients with ankylosing spondylitis
Revista Brasileira De Reumatologia, 53(3):
Occupational and Environmental MedicineAdjuvant occupational therapy improves long-term depression recovery and return-to-work in good health in sick-listed employees with major depression: results of a randomised controlled trialOccupational and Environmental Medicine
Quality of Life ResearchEvaluation of a role functioning computer adaptive test (RF-CAT)Quality of Life Research
Bmc Public HealthAn intervention program with the aim to improve and maintain work productivity for workers with rheumatoid arthritis: design of a randomized controlled trial and cost-effectiveness studyBmc Public Health
Current Opinion in RheumatologyEmployment and work disability in rheumatoid arthritisCurrent Opinion in Rheumatology
International Journal of Rehabilitation ResearchThe cross-cultural adaptation of the Work Role Functioning Questionnaire in Canadian FrenchInternational Journal of Rehabilitation Research
Journal of Occupational and Environmental MedicineStanford Presenteeism Scale: Health Status and Employee ProductivityJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineEffect of Health Insurance on Workplace Absenteeism in the U.S. WorkforceJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineObesity and Presenteeism: The Impact of Body Mass Index on Workplace ProductivityJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Cost of Poor Sleep: Workplace Productivity Loss and Associated CostsJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineA Multi-Worksite Analysis of the Relationships Among Body Mass Index, Medical Utilization, and Worker ProductivityJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe World Health Organization Health and Work Performance Questionnaire (HPQ)Journal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineDo Long Workhours Impact Health, Safety, and Productivity at a Heavy Manufacturer?Journal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineBaseline Characteristics of Workers at Ten New York City Employers Recruited for a Private-Public Research CollaborativeJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineMeasures of Cognitive Function and Work in Occupationally Active Breast Cancer SurvivorsJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Association Between Health Risk Change and Presenteeism ChangeJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Association of Health Status, Worksite Fitness Center Participation, and Two Measures of ProductivityJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineWhat Does Research Tell Us About Depression, Job Performance, and Work Productivity?Journal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineUsing Self-Reports of Symptom Severity to Measure and Manage Workplace DepressionJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicinePredictors of Successful Work Role Functioning After Carpal Tunnel Release SurgeryJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineA Method for Imputing the Impact of Health Problems on At-Work Performance and Productivity From Available Health DataJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineMeasuring Productivity Loss Due to Health: A Multi-Method ApproachJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineImpact of Nighttime Awakenings on Worker Productivity and PerformanceJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Novartis Health Index: A Method for Valuing the Economic Impact of Risk Reduction in a WorkforceJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineUsing Routinely Collected Data to Augment the Management of Health and Productivity LossJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineHealth and Work Productivity Assessment: State of the Art or State of Flux?Journal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Association of Medical Conditions and PresenteeismJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Clinical and Occupational Correlates of Work Productivity Loss Among Employed Patients With DepressionJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineMaking the Business Case for Health and Productivity ManagementJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Application of Two Health and Productivity Instruments at a Large EmployerJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Burden of Pain on Employee Health and Productivity at a Major Provider of Business ServicesJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineWork Productivity in Brain Tumor SurvivorsJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineBreast Cancer Survivors at WorkJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Association of Health Risks With On-the-Job ProductivityJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineA Web-Based Approach to Managing Stress and Mood Disorders in the WorkforceJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineProductivity Losses Related to the Common ColdJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineValidating Self-Reported Measures of Productivity at Work: A Case for Their Credibility in a Heavy Manufacturing SettingJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Burden of Allergies—and the Capacity of Medications to Reduce This Burden—in a Heavy Manufacturing EnvironmentJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineImpaired Work Performance Among Women With Symptomatic Uterine FibroidsJournal of Occupational and Environmental Medicine
Journal of Occupational and Environmental MedicineThe Association Between Beliefs About Low Back Pain and Work PresenteeismJournal of Occupational and Environmental Medicine
Journal of Orthopaedic TraumaWhen Is a Fracture Healed? Radiographic and Clinical Criteria RevisitedJournal of Orthopaedic Trauma
Journal of Trauma and Acute Care SurgeryEarly Predictors of Long-Term Work Disability After Major Limb TraumaJournal of Trauma and Acute Care Surgery
Orthopaedic NursingOutcomes Measurement for Patients With Low Back PainOrthopaedic Nursing
Work productivity; chronic disease and employment; disability.
© 2001 Lippincott Williams & Wilkins, Inc.
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