Taiwanese Version of the Work-Related Quality of Life Scale for Nurses

Translation and Validation

Abstract

Background: 

The shortage of professional nurses is a global issue of critical importance. Improving the retention and recruitment of nurses is necessary to reduce this shortage. The ability to measure the quality of work life (QWL) of nurses is important to understand the current QWL status among nurses and to develop appropriate improvement strategies. The two instruments that are currently used in Taiwan both require excessive amounts of time to complete. Furthermore, the results that these two instruments generate are not easily interdisciplinary and international comparisons.

Purpose: 

The aims of this study were to translate into Chinese the English version of the Work-Related Quality of Life Scale (WRQoL) that was developed by Van Laar, Edwards, and Easton (2007) and then to determine the reliability and validity of this Chinese-version scale in terms of measuring the QWL of nurses in Taiwan.

Methods: 

The WRQoL was translated from English into Chinese using forward-translation with group discussions, back-translation, and verification of conceptual equivalence. Concurrent validity, test–retest reliability, and internal consistency reliability were determined in two samples of nurses (n = 30 and n = 213 for Phases 1 and 2, respectively) from a medical center in Taiwan during September 2009.

Results: 

The 23-item Taiwanese version of the WRQoL showed satisfactory concurrent validity with a Taiwanese QWL scale (correlation = .75). The 3-week test–retest reliability was .89, and the Cronbach’s alpha was .88, indicating high internal consistency reliability.

Conclusions/Implications for Practice: 

The Taiwanese version of the WRQoL is acceptable for measuring the QWL of nurses in Taiwan. Larger scale studies are recommended for confirmatory factor analysis. This tool may be used for human resources management and policy-making applications, providing the potential to help retain and recruit nurses in Taiwan. Furthermore, the Taiwanese-version scale may be used to compare work-related quality of life between Taiwanese nurses and their counterparts overseas.

Introduction

Nurses account for the largest number of staffs in most healthcare systems. The contributions that nurses make have been recognized as essential for the delivery of safe and good-quality care (^{Aiken, Clarke, Sloane, Sochalski, & Silber, 2002; Burnes Bolton et al., 2007}). The aging of the world’s population and the acute healthcare needs of the older adults are increasing the workload of nurses (Liu, Lam, Fong, & Yuan, ²⁰¹²). Furthermore, the poor working conditions faced by professional nurses are exacerbating the chronic nursing shortage (^{Nardi & Gyurko, 2013}). This shortage of nurses, caused by both growing demand and shrinking supply, is one of the most critical issues in healthcare worldwide.

Taiwan faces a serious shortage of nurses. The turnover rate of qualified nurses is high: only 60% of licensed nurses stay in clinical nursing jobs, and 63.3% have considered changing their profession (^{Chang, Yu, Chao, Chen, & Tien, 2005}). In terms of demand, a recent survey reported that more than 90% of hospitals in Taiwan have difficulty recruiting and retaining a sufficient number of nurses (^{Lin, Hung, Kao, & Lu, 2013}). It is clear that new strategies are required to improve recruitment and retention levels (^{Buchan, 2002; Buchan & Sochalski, 2004}).

Improving the quality of work life (QWL) is one strategy for enhancing the recruitment and retention of employees (^{Hsu & Kernohan, 2006; Huang, Lawer, & Lei, 2007; Korunka, Hoonakker, & Carayon, 2008}). QWL reflects the subjective perceptions of the respondent toward his or her work, organization, and employer (^{Vagharseyyedin, Vanaki, & Mohammadi, 2011}). Therefore, understanding how nurses feel about their work environment and identifying those factors that relate negatively to QWL will provide information that may be used to improve the work environment to enhance nurse retention. Therefore, a sensitive measurement is required to enable nurse administrators to assess the QWL of nurses.

An effective QWL instrument is not currently available in Taiwan. The Work-Related Quality of Life Scale (WRQoL), a QWL scale for healthcare professionals, was developed for use in the United Kingdom (^{Van Laar, Edwards, & Easton, 2007}). This scale referenced data from a large sample of healthcare workers, which permits comparisons of QWL across different disciplines. Different-language versions of the WRQoL are currently used in countries such as Singapore (^{Zeng, 2011}), Turkey (^{Duyan, Aytac, Akyildiz, & Van Laar, 2013}), and Uganda (^{Opollo, Gray, & Spies, 2014}), which allows for WRQoL results to be compared internationally. Therefore, the purposes of this study were to translate the WRQoL from English into Chinese and then to evaluate the reliability and validity of this Chinese-version instrument in measuring the QWL of nurses in Taiwan.

Quality-of-Work-Life Measurements

Job satisfaction, one widely used measure of QWL, is often assessed using either the intent to leave or the likes and dislikes of employees (^{Brooks et al., 2007}). However, these measures are somewhat imprecise, as up to 30% of the variance in job satisfaction is attributable to personality, a factor that nurse administrators cannot change (^{Brooks & Anderson, 2004}). A more reliable measure would assess the relationships between employees’ stress levels, work environment, and organizational commitment.

Job satisfaction is a concept that applies solely to the workplace domain. A broader concept of job-related experience is QWL, which is similar to employee well-being (^{Chen & Farh, 2000; Lawler, 1982}). The assessment of well-being is a complex process that encompasses not only job satisfaction but also personal life, family life, and physical and mental health (^{Danna & Griffin, 1999}). QWL has become an important issue in nursing because improving QWL has been shown to improve recruitment, retention, work performance, productivity, and patient outcomes (McGillis ^{Hall & Kiesners, 2005; Hsu & Kernohan, 2006; Vagharseyyedin et al., 2011}).

Quality-of-Work-Life Instruments in Taiwan

Two instruments are currently used to measure the QWL of nurses in Taiwan. One instrument is the Chinese Quality of Nursing Work Life Scale that was developed using a phenomenological approach with clinical nurses (^{Su & Shieh, 2002}). This 57-item scale has 13 dimensions: work environment, compensation, benefits, promotion, training and development, work itself, leadership of immediate boss, interpersonal interactions, communication, organizational system, organizational atmosphere and culture, work hours and workload, and family and social factors. This scale has been applied in different healthcare settings and has shown good validity and reliability (^{Chuang, 2008; Fang, 2006; Yu, 2009}). Although this scale is appropriate for measuring QWL among nurses in Taiwan, it is overly time consuming to complete, making it difficult to administer effectively to busy nurses.

The second scale that is used to measure QWL in Taiwan is the 53-item Assessment Chart for Quality of Work Life, which has eight dimensions (^{Lin, Peng, Lin, & Hong, 2006}). This scale, used to assess all healthcare workers, is also lengthy to administer and does not assess the dimension of work–home interface, which is an important component of the QWL of nurses because nursing remains a female-dominated profession. Thus, the absence of a work–home interface dimension limits the scope of this scale as a measure of nurses’ QWL. Furthermore, the large number of items in both of the abovementioned scales makes them impractical for evaluating large samples of nurses. Finally, neither scale allows for international comparisons. Thus, a concise, sensitive instrument is needed to assess the QWL of Taiwanese nurses and to allow for the comparison of results with QWL measurements conducted on nurses in other countries.

The Work-Related Quality of Life Scale

The WRQoL is widely used to measure the QWL of healthcare professionals around the world (^{Van Laar et al., 2007}). This evidence-based measure has been translated into more than eight languages. On the basis of ^{Maslow’s (1954)} need satisfaction theory and ^{Herzberg’s (1966)} two-factor theory, the WRQoL incorporates a broad range of concepts, including work and nonwork factors. The original 23-item WRQoL measures employees’ QWL. Responses are rated on a 5-point Likert scale, with higher scores indicating higher levels of QWL. This scale has six dimensions: (a) job and career satisfaction, (b) general well-being, (c) stress at work, (d) control at work, (e) working conditions, and (f) home–work interface. The WRQoL is psychometrically robust, with an overall Cronbach’s alpha of .91 and an excellent goodness of fit (comparative fit index: 0.94, goodness-of-fit index: 0.93, normed fit index: 0.92, and root mean square error of approximation: 0.05; ^{Van Laar et al., 2007}). In addition, this scale has been validated for nurses, healthcare workers (^{Van Laar et al., 2007}), and higher education employees (^{Edwards, Van Laar, Easton, & Kinman, 2009}). The scale is easy to apply and allows for interdisciplinary and international comparisons. The original WRQoL scale has been shown to be a valid and reliable instrument, making it an appropriate scale for translation into Chinese for use in Taiwan.

Issues in Scale Translation

The quality of scale translation depends on the validity and accuracy of the translation (^{Maneesriwongul & Dixon, 2004}). Translation validity and accuracy both play pivotal roles in cross-cultural research, ensuring that the results obtained from different populations are not because of translation errors (^{Maneesriwongul & Dixon, 2004}). The accuracy of the translation is also important to insure that the resulting scale is culturally acceptable (^{Cha, Kim, & Erlen, 2007}).

One form of translation validity is equivalence, which means that the original scale and the translated scale measure the same construct (^{Chang, Chau, & Holroyd, 1999}). In translating a scale, equivalence encompasses five dimensions: content, semantic, technical, criterion, and conceptual (^{Chang et al., 1999; Flaherty et al., 1988}). The four techniques that are frequently used in cross-cultural research to ensure equivalence include back-translation, bilingual techniques, committee approach, and pilot testing/pretesting (^{Brislin, Lonner, & Thorndike, 1973}).

Furthermore, the validity of a translated instrument depends on the translator. To select qualified translators, three criteria have been suggested (^{Hambleton, 1993}): (a) familiarity with and competence in both the target and source languages, (b) expertise in the subject matter, and (c) some training in instrument development and the principles of writing good test items. Translators are an integral part of a well-established instrument-translation model for cross-cultural research (^{Brislin et al., 1973}). Brislin et al.’s model uses a bilingual translator to translate the scale from the original language into the target language (forward-translation), a second bilingual translator to translate the instrument from the target language back into the original language (back-translation), and a third translator to compare these two versions for conceptual equivalence. If the two scales are not equivalent, the procedure is repeated using a new set of bilingual translators (^{Brislin et al., 1973}). Because this model requires several translators, it may not be feasible in resource-limited settings.

A more recent model for scale translation addresses the problem caused by requiring several translators (^{Cha et al., 2007}) by reducing the number of translators using group techniques. This model first has three bilingual translators translate the original scale into the target language independently and then has them meet to discuss their translations until a consensus is reached regarding the finalized scale in the target language. One bilingual translator then performs the back-translation, and an English-speaking person with a cross-cultural background compares the original and back-translated English version for conceptual equivalence. If those two scales are not equivalent, the differences are then explained to the bilingual translators, after which the same group of translators and experts repeat the procedure until the forward- and back-translated scales are equivalent (^{Cha et al., 2007}). This is the model of translation that was used in this study.

Methods

Design

A two-phase descriptive and correlational design was used to translate the English version of the WRQoL scale (^{Van Laar et al., 2007}) into Chinese. The validity and reliability of the translated WRQoL scale were determined by correlating the scores from the WRQoL with the scores from the Chinese Quality of Nursing Work Life Scale (^{Su & Shieh, 2002}).

Translation of the Work-Related Quality of Life Scale

Five bilingual translators translated the WRQoL scale from English into Chinese using the method of ^{Cha et al. (2007)}. The first three translators, who performed the forward translation, were nurses who were familiar with QWL and scale translation (one holds a master’s degree in clinical nursing and two hold doctoral degrees in nursing administration from schools in the United States). The fourth translator, who performed the back-translation, was a senior director in the nursing department. The fifth translator, who verified the translated scale, was a lecturer in English at a Taiwan university with a master’s degree in English from the United States. The three forward-translators translated the WRQoL scale from English into Chinese independently. They discussed their forward-translated WRQoL scales until they reached a group consensus on the final WRQoL scale in Chinese. The fourth bilingual translator then back-translated this Chinese-version scale into English. The fifth translator (our English expert) verified the translation by comparing the back-translated scale with the original WRQoL scale for content equivalence, for discrepancies or inaccuracies in translation, and for any misinterpretations of meaning. If the back-translated WRQoL scale was found to lack semantic or content equivalence and/or cross-cultural agreement with the original WRQoL scale, the back-translated version was returned for additional forward-translation, group discussion, and back-translation. This process was repeated until the English expert determined that the back-translation was equivalent to the original WRQoL scale. This verified translation was considered to be the first draft of the Taiwan-version WRQoL scale (WRQoL-T).

Validation of the Taiwanese-Version Work-Related Quality of Life Scale

The draft of the WRQoL-T was validated using a two-phase test (Figure 1). Phase 1 analyzed the face validity and test–retest reliability of the WRQoL-T, whereas Phase 2 tested the concurrent validity and internal consistency reliability of the scale.

Figure 1: Diagram of translation and validation processes. WRQoL=work-related quality of life scale; WRQoL-T=work-related quality of life scale- Taiwan version

Sample and Data Collection

Two samples of registered nurses were recruited from a 3000-bed medical center in Taiwan in September 2009. For Phase 1, the draft of the WRQoL-T was tested on a convenience sample of 30 nurses who were recruited from the surgical and medical wards by two nurse managers. For Phase 2, a list of 300 potential participants was generated using a simple random sampling method. Each potential participant received a package that included an invitation to participate with a description of the study, the WRQoL-T scale, the Chinese Quality of Nursing Work Life Scale (^{Su & Shieh, 2002}), a demographic survey, and a return envelope. Participants were asked to complete and return the questionnaires and surveys within 2 weeks. The completed forms were returned directly to the first author via the hospital’s documents delivery system. This author examined each returned questionnaire. If more than 5% of the data were incomplete or appeared to be systematically missing, the questionnaire was discarded. Any missing values in the remaining questionnaires were imputed by mean or mode.

Ethical Considerations

The institutional review board of the hospital approved this study. The information package sent to participants described the study purpose, the procedures involved, the rights of participants (including guaranteed anonymity), and the contact information for the first author. Participants completed the questionnaires anonymously to ensure their comfort in answering questions involving sensitive information regarding their perceptions of the work environment. Those who returned the questionnaires were assumed to have consented to participate in this study.

Data Analysis

Participant characteristics and scale scores were analyzed using descriptive statistics (means, standard deviations, frequencies, and percentages). The face validity and 3-week test–retest reliability of the WRQoL-T were determined using a two-tailed Student’s t test. Criterion validity was evaluated using correlations between scores on the WRQoL-T and the Chinese Quality of Nursing Work Life (^{Su & Shieh, 2002}) scales. Internal consistency reliability of the WRQoL-T was evaluated using Cronbach’s alpha coefficient. Data were analyzed using SPSS 15.0 for Windows (SPSS Inc., Chicago, IL, USA).

Results

Participant Characteristics

In the two study samples, 30 nurses participated in Phase 1 (face validity and test–retest reliability), and 213 nurses participated in Phase 2 (validity and internal consistency reliability). The 213 nurses (representing a 71% response rate) had a mean age of 34.6 years (range = 23–59 years, SD = 8.9 years; Table 1). Most participants were female (97.7%) and had at least a bachelor’s degree (77.9%). They had worked as nurses, on average, for 10.8 years (range = 0.1–36.7 years, SD = 8.7 years), with an average of 5.82 years in their current unit (range = 0.1–30.0 years, SD = 6.1 years). Participants worked in a broad range of areas, with the largest proportion working in wards (38.0%), followed by intensive/emergency care (27.7%), surgery (12.2%), the outpatient department (11.7%), and other units (10.3%).

TABLE 1: Demographic Characteristics of Phase 2 Participants (N = 213)

Translation of the Taiwanese-Version Work-Related Quality of Life Scale

The translation process from English to Chinese emphasized establishing the cross-cultural reliability necessary to use the WRQoL in Taiwan. Although the three translated versions of the forward-translated scale each used slightly different terminology, the translators reached consensus after group discussion. The English expert found the back-translated and original versions of the WRQoL-T to be equivalent and approved the back-translated version without any further modifications. All translators approved the draft-version WRQoL-T before validity and reliability testing.

Quality of Work Life Among Nurses in Taiwan

Phase 1: face validity and test–retest reliability

Phase 1 was implemented to pretest the face validity (readability) and stability (test–retest reliability) of the WRQoL-T. Face validity was deemed to be adequate based on participants’ ability to read and understand all of the 23 scale items. The participants took an average of 6 minutes to complete the WRQoL-T. The 3-week test–retest reliability indicated good stability, with a correlation coefficient of .89 (p < .001).

Phase 2: validity and internal consistency reliability

Validity denotes the scientific utility of a scale in terms of how well that scale measures what it purports to measure (^{Nunnally & Bernstein, 1994}). The validity of the WRQoL-T scale was determined by criterion validity with the Chinese Quality of Nursing Work Life Scale (^{Su & Shieh, 2002}). The correlation coefficient for the total WRQoL-T scale was .75 (p < .001), suggesting that the scale is a valid measure of the QWL of nurses in Taiwan because the Chinese Quality of Nursing Work Life Scale is specifically designed to be administered to nurses who work in Taiwan. The item-to-total scale correlations ranged from .14 to .68 (Table 2), and the internal consistency reliability for the WRQoL-T was strong, as indicated by a Cronbach’s alpha of .88. The internal consistency reliability for each subscale was also high: .77 for job and career satisfaction, .84 for general well-being, .71 for home–work interface, .70 for stress at work, .80 for control at work, and .68 for working conditions.

TABLE 2: Item Statistics for the Taiwanese Work-Related Quality of Life Scale and Item-to-Total Correlation (N = 213)

The mean total WRQoL-T score for nurse participants was high (Table 3): 3.40 of 5 (range = 1.74-5.00, SD = 0.42). This score is somewhat lower than the WRQoL scores for English healthcare workers after standardization (D. Van Laar, personal communication). Nurse participants’ WRQoL-T subscale scores were also above average (higher than the Likert scale midpoint). The lowest subscale score was 3.25, for general well-being, and the highest was 3.57, for job and career satisfaction. These results indicate that the QWL of participants was moderate to high. No ceiling or floor effects were found.

TABLE 3: Participants’ WRQoL-T Total and Subscale Scores (N = 213)

The demographic variables of marital status and job position were found to affect the WRQoL-T scores of participants (Table 4). Married nurses earned a higher mean total score than unmarried nurses (p = .009), and nurses who worked in surgery earned a lower mean total score than those working in any other unit (p = .009) and the lowest mean total score of all participants. Furthermore, nurse managers had the highest mean total WRQoL-T score (p < .001) of all participants. This positive relationship held true for other positions on the nursing ladder, with higher positions on the ladder earning higher mean total scores.

TABLE 4: WRQoL-T Scores by Participants’ Demographics (N = 213)

Discussion

The results of this study indicate that the WRQoL-T has good overall reliability and validity to assess the QWL of nurses in Taiwan. Furthermore, the 23-item WRQoL-T is much shorter than the two scales that are currently used in Taiwan to assess the QWL of nurses (^{Su & Shieh, 2002}) and of other health workers (^{Lin et al., 2006}), making the WRQoL-T more acceptable for administrators to use in assessing the QWL of busy nurses. In translating the original WRQoL, we adopted the process of scale translation described by ^{Cha et al. (2007)} because it is rigorous and better suited for low-resource settings, as it requires fewer translators than Brislin et al.’s method (^{Brislin et al., 1973}). Qualified translators were selected not only for their bilingual skills but also for their knowledge of the WRQoL scale and their experience with scale translation. Translators who are familiar with an original scale before translation have been found to generate translated scales that are marked by relatively high levels of conceptual equivalence with the original scale (^{Sidani, Guruge, Miranda, Ford-Gilboe, & Varcoe, 2010}). Moreover, the format of the WRQoL-T is the same as the original WRQoL scale, that is, 23 questions that use a 5-point Likert scale, thus ensuring technical equivalence.

The WRQoL-T is more appropriate for assessing the QWL of nurses in Taiwan than a similar scale that was recently translated into Chinese for use in China (^{Lin, Chaiear, Khiewyoo, Wu, & Johns, 2013}). Although the latter scale is also in Chinese, it uses simplified Chinese characters rather than the traditional characters that are used in Taiwan, Hong Kong, and Macau. China and Taiwan are not only culturally different, but terminology also frequently differs, similar to the differences in English usage among various English-speaking nations. Another important difference between the two Chinese-language versions is that the simplified Chinese version was translated from the WRQoL-2, which has 36 items and a seventh subscale—employee engagement (^{Van Laar, 2013}). This difference makes it difficult to make international comparisons with scores from the more widely translated original WRQoL scale. Furthermore, it remains unclear whether the original WRQoL-2 is adequately sensitive to the work life of nurses. Finally, the simplified Chinese-version scale is not appropriate for use in Taiwan, which further illustrates the importance of maintaining translation and semantic equivalence in translated scales.

Another strength of the WRQoL-T is that the accuracy of the translation was pretested on a small sample of the target population to help identify any difficulties with understanding or interpreting items, as recommended by ^{Brislin et al. (1973)}. The pretest group of 30 nurses reported no reading or interpretation problems. The 3-week test–retest reliability was .89 (p < .001), which is well above the .70 considered acceptable for a new instrument (^{Nunnally & Bernstein, 1994}), indicating good stability of the WRQoL-T scale.

The WRQoL-T also had an overall alpha coefficient of .88, which is approximately the same as that for the original WRQoL (^{Van Laar et al., 2007}), indicating excellent internal consistency reliability. The subscale reliabilities ranged from .68 to .84, which are slightly lower than those for the original WRQoL (^{Edwards et al., 2009; Van Laar et al., 2007}), but still acceptable (^{Nunnally & Bernstein, 1994}).

Demographic variables were shown to affect WRQoL-T significantly, suggesting that the WRQoL-T may be used to detect differences in QWL among different groups of nurses. For example, the total mean WRQoL-T score for surgical nurses was significantly lower than the total mean scores for nurses working in other units, suggesting that surgical nurses may be appropriate targets for work-environment improvement initiatives. Improvements may then be evaluated by administering the WRQoL-T, with increased scores indicating better QWL that is attributable to the work-environment improvements. Thus, the WRQoL-T may be used as a screening tool to assess and improve the QWL of nurses in Taiwan. Whether the WRQoL-T may be used to assess QWL in other healthcare professionals requires further validation.

Conclusions

The results of this study suggest that the WRQoL-T scale is a valid instrument for measuring the QWL of nurses in Taiwan. WRQoL-T scores correlated well with scores obtained using the Chinese Quality of Work Life Scale (^{Su & Shieh, 2002}), which is currently widely used in Taiwan. This correlation confirms that the WRQoL-T scale has adequate sensitivity for nurses. The original WRQoL scale has the advantage of being designed to measure the QWL of all healthcare professionals, suggesting that the WRQoL-T scale may be adapted and validated for use with other healthcare professionals in Taiwan, which will allow scores to be compared across disciplines. Finally, the original WRQoL has been translated into several languages, which offers the potential of comparing the WRQoL-T scores of Taiwanese nurses with those of nurses from other countries.

Practical Implications

Nurse administrators may use the WRQoL-T to measure the QWL of Taiwanese nurses. Better understanding the state of QWL among Taiwanese nurses is critical to developing strategies to improve QWL and to increase nurse retention. Furthermore, improvements in nurses’ QWL may enhance recruitment efforts by both attracting former nurses back to nursing and encouraging young people to consider pursuing a nursing career (^{Buchan & Sochalski, 2004}). Furthermore, the ability to compare WRQoL-T scores between Taiwanese nurses and nurses in other countries will provide critical evidence needed by nursing leaders to strive for better QWL when negotiating with employers or when lobbying on work-related issues. Finally, using the WRQoL-T to monitor the QWL of nurses will benefit patient care because quality of care has been linked to the QWL of nurses (McGillis ^{Hall & Kiesners, 2005; Vagharseyyedin et al., 2011}).

Study Limitations

This study is impacted by several limitations. First, the item-to-total scale score correlations for two items were unacceptable: Item 7 (“I often feel under pressure at work”) had a correlation of .14, and Item 9 (“I often feel excessive levels of stress at work”) had a correlation of .16. Item-to-total correlations < .30 suggest that items are not relevant to the concepts measured (^{Nunnally & Bernstein, 1994}). These two items are both related to work stress, suggesting that “pressure” and “stress” have different meanings in Western and Taiwanese cultures. Nurses in Taiwan may feel that a certain amount of stress at work is normal or acceptable and is thus not perceived as a negative quality. Further research is required to clarify the meaning of these statements. Second, we included only WRQoL-T questionnaires with less than 5% of the data missing in our analysis. However, reporting missing data has been recommended as a strategy to increase the rigor of translated scale testing (^{Fox-Wasylyshyn & El-Masri, 2005}). Nevertheless, the impact of this limitation may be minimal because we used the mean to impute missing values—a strategy that has been shown to have little impact on the results when missing values comprise < 5% of the sample (^{Tabachnick & Fidell, 2007}). Finally, we did not perform confirmatory factor analysis because our Phase 2 sample (n = 213) was smaller than the minimum of 300 recommended for confirmatory factor analysis of a 23-item scale (^{Tabachnick & Fidell, 2007}). Thus, we recommend that future studies with larger sample sizes be used to test the construct validity of the WRQoL-T.

Acknowledgments

This study was funded by the Taipei Veterans General Hospital under Grant number V98-A-149. The authors would like to thank Professor Wei Wang who back-translated the Work-Related Quality of Life scale into English.