BACKGROUND AND PURPOSE
Over the last 20 years in the USA, concerns regarding safe patient handling (SPH) have received increased attention among health professionals performing patient handling tasks.1,2 Olkowski and Stolfi3 recently surveyed 192 acute care physical therapists (PTs) and found that 91.1% of those who responded to the survey are trained to use SPH equipment and practices and have positive perceptions regarding SPH. SPH can be defined as the judicious use of assistive technology (eg, electro-mechanical equipment and lift-assist devices), ergonomic principles, and other resources (eg, lift teams) to maximize patient and caregiver safety for patient handling tasks such as lifts, transfers, and repositioning.1 In contrast, traditional nontherapeutic patient handling tasks for lifts and transfers have been performed manually by health care providers with a foremost emphasis on use of sound body mechanics. A recent systematic review of occupational musculoskeletal injuries in the health care environment found that patient handling was the most common occupational factor in the cause of work-related injuries among PTs and nursing practitioners. Lifting and transfer of patients was the largest reported occupational cause of practitioner injuries.4 Campo and colleagues5 found a 1-year incidence rate of work-related musculoskeletal disorders (WMSDs) of 20.7% among PTs in the US and noted that many of these injuries were due to patient handling tasks. Darragh and colleagues6 surveyed 1,158 occupational therapists (OTs) and PTs in Wisconsin and found that patient transfers and lifts were associated with 58% of all injuries reported.
Using a phenomenological approach to explore the meaning of work-related pain in PTs and OTs, Campo and Darragh7 noted that all therapists were concerned about their potential clinical longevity due to work-related pain. Such injuries may also occur during physical therapist education, as Nyland and Grimmer8 found that physiotherapy students’ risk of low back pain increased progressively with the year of study. WMSDs have serious consequences to clinicians, employers, and the health care system as a whole. As many as 1 in 6 PTs have reportedly changed professions as a result of a WMSD injury.9 In addition, employers and insurance companies are left to deal with significant direct and indirect costs due to work-related injuries that totaled $194 billion in 2007.10 Worker's compensation covers less than 25% of these costs, leaving the burden shared through all members of society and contributing significantly to the cost of health care.10
Use of assistive technology and biomechanically sound lifting and transfer techniques, principles of SPH practice, have been shown to reduce both the rate of injury and the economic burden associated with lifting injuries.11–14 Although SPH techniques are often taught in health professions classrooms, a discrepancy between education and clinical practice appears to persist.15–18 Students found clinical settings were not frequently supportive of SPH techniques.16–21 For example, Green19 asked nursing students to reflect on their performance of SPH practices throughout their clinical experiences and found that allowing students to develop a heightened sense of awareness through reflection on action enabled them to establish personal attitudes and the subsequent assertiveness to utilize SPH techniques. This type of reinforcement early in the education process is vital to protect students, as evidence shows that WMSDs are most frequent and significant within a PT's initial 4–5 years of work.22–24
Perhaps a dynamic, multi-disciplinary approach to promoting a safer work environment for health care workers could be most effective in changing SPH attitudes. Geiger25 examined the combined efforts of Israeli ergonomists and direct health care providers with regard to a safe patient handling and movement program spearheaded by physical therapists. Short-term outcomes included improved hospital-wide awareness of ergonomics, patient safety equipment, and a need for additional safety equipment. Long-term effects included reductions in ergonomic risk factors for musculoskeletal injury among hospital employees and physical therapists that were shown to be an essential component for the effectiveness of the ergonomic program due to their background in musculoskeletal injury, movement observation, and knowledge of kinesiology and biomechanical principles.25 Additionally, Wilson and colleagues13 examined the effectiveness of an 8-hour patient handling educational program for nursing assistants as taught by physical therapy and nursing educators, and found that overall confidence in patient handling skills improved significantly.
Finally, recognition that patient handling tasks (eg, lifting and transfers) are a source of injury to health care providers plays a role in advancing the safe patient handling and movement initiative.5,9,26–28 The success of SPH initiatives for the physical therapy profession may depend on the likelihood that student PTs see themselves taking on leadership roles as advocates and promoters of SPH after graduation. Therefore, it is important to discern contributing factors such as knowledge, intent, and attitude that may motivate student PTs to become future advocates for a transition from manual handling practices to the intentional use of SPH. Thus, the purpose of this study was: (1) to determine the impact of both didactic and clinical education on attitudes, intentions, and behaviors regarding patient handling tasks involving lifts and transfers, and (2) to identify whether student physical therapists’ attitudes, intentions, and behaviors regarding patient handling tasks are indicative of a willingness to take an advocate role in promoting and performing SPH in future clinical practice
As illustrated in Figure 1, the hypotheses for this study were developed from the theory of reasoned action (TRA) and a proposed model where attitudes drive intentions, which then drive behaviors.29,30
The 5 tested hypotheses were: (1) The mediated relationship described by TRA will hold with respect to SPH attitudes, intentions, and subsequent clinical behaviors. Support for this hypothesis would both replicate the work of other researchers31,32 and validate the data described in the current research. (2) Didactic education in SPH will be positively related to SPH behaviors in practice, and this link will be mediated by the subject's attitude toward SPH. (3) Didactic education in SPH will be positively related to leadership expectations in practice, and this link will be mediated by the subject's attitude toward SPH. (4) Clinical experiences related to SPH will be positively related to SPH in practice, and this link will be mediated by the subject's attitude toward SPH. (5) Clinical experiences related to SPH will be positively related to leadership expectations in practice, and this link will be mediated by the subject's attitude toward SPH.
The sampling population for this study consisted of student PTs enrolled in any of the 227 CAPTE-accredited physical therapist education programs in the US and Puerto Rico, as listed on the American Physical Therapy Association (APTA) website in November, 2012. Inclusion criteria for participation in this study were matriculation as a degreeseeking student PT and completion of a patient handling curriculum module. Exclusion criteria were lack of completion of a patient handling curriculum module and/or lack of a clinical education rotation. Participation was voluntarily, with no direct compensation benefits. A link to an online survey was sent to the program directors for CAPTEaccredited programs, along with a request to forward this survey link to their student PTs. As incentive, individuals who fully completed the survey and indicated that they wished to be included were entered into a randomized drawing to win a $10 gift card. Table 1 lists descriptive statistics for the responses that were generated. Participants (n = 291) represented 23% of CAPTE-accredited programs, 54% of states in the US and Puerto Rico.
This was a non-experimental survey study. Cross-sectional data were collected using an electronic questionnaire.
A 50-item survey instrument was developed to assess the type of patient handling education student PTs received, whether or not they used these techniques in clinical practice during their clinical education, and their intention to assume a leadership role in patient handling practices as entry-level practitioners. The survey consisted of 7 sections: (1) description of the study followed by provision of informed consent, (2) study definitions of manual patient handling and SPH methods, with illustrations of each performing a sit-to-stand transfer, followed by categorical questions regarding what forms of patient handling instruction they received in either classroom or laboratory settings, (3) 12 opinion items regarding their patient handling instruction in both didactic and clinical education setting, (4) 11 opinion items regarding their use of SPH practices in clinical education settings, (5) 17 opinion items regarding current attitudes, intentions, and beliefs regarding patient handling techniques and future practice as a PT, as adapted from studies by Jenner, Watson, Miller, Jones, Scott,34 and Johnson and Hall,35 (6) 8 opinion items regarding PT education received at their institution, and (7) demographic information, including gender, enrollment year in their physical therapist education program, and type of entry-level degree. All opinion items used a 7-point Likert scale (strongly agree, agree, somewhat agree, neither agree nor disagree, somewhat disagree, disagree, and strongly disagree). Components of the survey instrument were based on the theory of reasoned action (TRA).29,30 Face and content validity were evaluated using a small sample of second-year students at Grand Valley State University (GVSU), with revisions made to improve comprehension and eliminate bias wherever possible. Reliability was assessed by computing Cronbach's alpha for each of the constructs. The alpha for clinical SPH (.90), classroom SPH (.95), SPH intentions (.92), and SPH leadership intentions (.95) were all well beyond recommended limits. However, SPH behaviors (.56) and SPH attitudes (.68) were lower than would be expected. This discrepancy is likely explained by the fact that these measures included reverse coded items that have been shown to impact reliability calculations.31 Pilot testing indicated that participants completed the survey in approximately 25 minutes. The Appendix lists only those survey items included in the analyses.
Data Collection Procedures
The list of 227 CAPTE-accredited physical therapist education programs included on APTA's website provided email addresses of directors or other contact persons for each program. Each individual listed received an email with a description of the study and an invitation to participate, as well as a request to forward the invitation and Qualtrics® survey link to the faculty member(s) who were responsible for teaching patient handling in the curriculum. Those faculty members were asked to forward the invitation and survey link to their students. Informed consent consisted of a thorough explanation of the purpose of the study, methods, risks, participant requirements, and benefits of participation. After informed consent was given, subjects who agreed to participate in the study were asked to complete the survey, which was available from November 15, 2012 until December 21, 2012.
In a seminal paper on mediation, Baron and Kenny36(pp 1176) suggest that, “A variable functions as a mediator when it meets the following conditions: (a) variations in levels of the independent variable (IV) significantly account for variations in the presumed mediator (i.e., Path a), (b) variations in the mediator significantly account for variations in the dependent variable (DV) (i.e., Path b), and (c) when Paths a and b are controlled, a previously significant relation between the independent and dependent variables is no longer significant, with the strongest demonstration of mediation occurring when Path c is zero.” As illustrated in Figure 2, a mediator is a variable that explains part or all of a relationship between an IV and a DV. A mediator can be distinguished from a moderator, as a mediator generally explains how or why a certain relationship exists, while a moderator explains when a relationship will hold and when it will not.
All proposed hypotheses were tested using the bootstrap mediation test developed by Preacher and Hayes.37 The choice to use the bootstrap technique instead of the commonly used Baron and Kenny technique was made for 3 reasons. First, the bootstrap technique is capable of identifying different types of mediation (ie, competing mediation or indirect only mediation).28 Second, the bootstrap technique allows for testing hypotheses with relatively small sample sizes. While the sample used in the current research is not considered small, some researchers have recommended samples of 1,000 subjects to sufficiently test for mediation effects.37 Finally, the bootstrap test is replacing the Baron and Kenny test as the preferred method of mediational analysis in many fields like psychology and marketing. However, all of the mediation tests described below were also tested and found to be significant using the more traditional Baron and Kenny and Sobel approach.
The following analysis of mediation effects will apply commonly used terminology where the “a” path denotes the path between the IV and the mediator, the “b” path denotes the link between the mediator and the DV, and the “c” path is used to describe the link between the IV and the DV. In addition, “c” is used to describe the link between the IV and the DV while controlling for the proposed mediator (see Figure 2). Latent variables for the 6 constructs used in these data were computed by averaging their respective items. In order to test whether the TRA model fit with these data, the variables in question (SPH Attitudes, SPH Intentions, and SPH Behaviors) were loaded into the multiple mediation macro provided by Andrew Hayes,38 and the results are reported as suggested by Zhao and colleagues.39 The macro works by taking 1,000 resamples from the data and calculating a confidence interval for the mediation effect (the product of the “a” path and the “b” path). The result of the first hypothesis test was a mean indirect effect that was positive and significant (a × b = 0.047), with a 95% confidence interval excluding zero (0.0265 to 0.07), indicating a significant mediation effect. A unit increase in attitude toward SPH increased intentions to use SPH techniques by 0.1959 units (P < .001). Holding attitude constant, a unit increase in intentions to use SPH increased actual SPH behaviors by 0.2399 units (P < .001). The direct effect between attitudes and behaviors (“c” path) was also significant (β = .087, P < .001). When controlling for the mediated effect, the link between attitudes and behaviors remained significant (P = .039), but the magnitude of the effect decreased substantially (β = .0337). Because the “c” path was not reduced to zero, this (and the other hypotheses tested) would be considered partial mediation using Baron and Kenny's terminology. The result for hypothesis 1 reveals that this data set is consistent with similar research showing that the TRA model is applicable in health professions research.
Table 2 shows the results of the same analysis applied to the remaining 4 hypotheses. As mentioned in hypothesis 2, these results show that SPH didactic training impacts SPH behaviors through the subject's attitude toward SPH. Hypothesis 3 was supported showing that SPH classroom training impacts SPH leadership expectations through the subject's attitude toward SPH. Hypothesis 4 was also supported, confirming that the link between clinical training and SPH patient handling was mediated by the subject's attitude toward SPH. Finally, with hypothesis 5, the notion that clinical training impacts a subject's SPH leadership expectations through their attitudes toward SPH was also supported. Table 3 lists specific survey items regarding barriers of safe patient handling practices in classroom and clinical education with their responses expressed as dichotomous outcome percentages. Agreement is indicated by responses of 1–3 (“strongly agree-somewhat agree”), with non-agreement indicated by responses of 4–7 (“neutral-strongly disagree”).
Results of this study support the theory of reasoned action, whereby student physical therapist attitudes regarding SPH did indeed significantly influence their intention and subsequent SPH behavior while enrolled in physical therapist education programs. For participating student PTs, both didactic instruction in the classroom and clinical education significantly impacted SPH attitudes and subsequent behaviors, as well as leadership expectations for advocacy of SPH. These findings may suggest that, in order to reduce the vast occurrence of musculoskeletal injuries incurred by both PTs and other health care professionals during patient lifting and transfers, SPH education needs to be emphasized and included in both classroom and clinical settings for student PTs. Such a goal may be accomplished when student PTs recognize the values and evidence-based support for SPH. Research by Swain and colleagues,17 in which students were questioned about their attitudes toward SPH and their intention to use SPH practice during clinical experiences, found that 85% of students did not believe SPH was useful in the workplace. In contrast, a recent study of student PTs by Stevenson and colleagues18 found that 52% of students who thought research evidence did not support the use of SPH principles still reported intention to follow SPH methods when a patient required a maximal assistance lift or mod-max assistance. They also found that 68% of those students who thought research evidence supported the use of SPH principles intended to use SPH methods in their future practice. However, the authors noted the existence of an education-practice gap in patient handling methodology among students, as evidenced by their finding that, while 61% of student PTs intend to follow SPH methods, only 26% of this group reported seeking SPH devices in the clinical setting.18
Since there is growing research showing that SPH programs are effective in reducing musculoskeletal injuries to health care workers,11,40–45 a change to further SPH education (both classroom and clinical) could alter attitudes and resultant behaviors with regard to SPH practices. For example, Geiger25 found advancement in ergonomics awareness and knowledge among staff members after selected staff received training in ergonomics for a therapist-driven SPH program in an Israeli general medical center. Other noted changes in staff behavior were better coordination of patient handling tasks between nursing and therapy staff, establishment of multi-disciplinary ergonomics teams to address WMSD problems, including patient handling tasks, and reduction of ergonomic risk factors for musculoskeletal injury among hospital staff.25 Recently, Olkowski and Stolfi4 found that a large majority (91.1%) of acute care PTs they sampled in their 2014 survey study are trained in SPH equipment and techniques, and not only use SPH equipment and practices, but have also developed positive perceptions regarding SPH. However, no mention was made whether any of the PTs included in the study received SPH education as part of their entry-level degree program.
Even if student PTs understood and appreciated the importance of SPH practice for their profession, remaining obstacles, such as an academic and clinical environment unsupportive of SPH, may still exist.17–18 When viewing the dichotomous response percentage data in Table 3, a majority of respondents felt that their classroom and laboratory experiences in their curricula were adequate for encouragement and instruction in the use of SPH. However, when considering their clinical education experience, their responses revealed diminished agreement to statements regarding orientation to SPH at their facility, encouragement and expectations of clinicians to use SPH, and the time to practice and use SPH when working with patients. Such barriers to adoption and use of SPH in clinical practice have been noted previously for nursing and other health professions.1,2,11–13 While similar results were found by Stevenson and colleagues for data collected during the 2010–2011 academic year, the gaps between responses to similar items used in this study were larger and less supportive of training and use of SPH in both the didactic and clinical settings.18 Thus, with comparison of responses to similar items in this earlier study, it appears that noticeable growth in knowledge and training in the use of SPH in both the didactic and clinical settings has occurred.
One suggestion to close the educationpractice gap for SPH is to utilize direct questioning methods to afford students the opportunity to reflect on the patient handling environment they are exposed to and the SPH practices they may be following. This can apply to case-based examples in the classroom or laboratory or involvement in clinical education. An example of this is illustrated in the study by Green,19 who found that promoting student reflection on their handling experiences allowed them to concretely formulate SPH values, as well as having a positive effect on their handling behaviors in spite of unsupportive environments. Wilson and colleagues13 also found that as nursing assistants learned more about the technical aspects of bed mobility, transfers, and ambulation techniques from physical therapist instructors in an 8-hour SPH program, their confidence and knowledge improved significantly. Any lasting effects of the educational program were not assessed.
Throughout history, it has been hypothesized that behaviors are driven by an individual's (deliberate or incidental) cognitive processes.46 This idea was central to the development of the TRA model (the theoretical basis for the current study), which states that attitudes drive intentions, which then drive behaviors. In some cases however, psychologists have found evidence for a reverse effect, where behaviors can drive an individual's attitude. Researchers have used cognitive dissonance as a theory to explain this pattern.47 For example, if a therapist displays competence with a certain technique for patient transfer, then he/she will likely develop a positive attitude toward the technique because of personal expectations. Our data show that the TRA model fits the data regarding attitudes and behaviors of young PTs, a finding consistent with related health professions research.16–20 Attitudes were shown to mediate subject behavior with respect to both didactic and clinical education. The established system, where educators are influential in shaping student attitudes and students actively participate in SPH behaviors, both in laboratory and clinic, is clearly a path toward creating advocates for SPH in the profession.
The authors recognize several limitations to this study. First, the inherent bias of the word “safe” used in our survey when describing different patient handling practices posed a limitation regarding common use of the phrase, “safe patient handling.” Accordingly, the acronym “SPH” was used throughout the survey to describe safe patient handling and movement, while the acronym “MPH” was used to describe traditional manual patient handling in an attempt to limit the bias of the word “safe.” Second, the data collection process did not allow the authors to account for potential selection bias of faculty members of the participating CAPTE-accredited programs. Faculty also may not have understood the benefits of SPH, as traditional manual patient handling (MPH) techniques have been taught for years and are potentially still viewed as the standard of practice despite recent evidence supporting SPH. Thus, the authors recognize a potential bias in the study results due to lack of interest or insufficient SPH practices within any given curriculum. Third, the authors chose to analyze the data using the TRA model rather than using the theory of planned behavior (TPB). The TPB model incorporates 2 additional constructs that drive intentions and attitudes. Although the TPB model provides a more complete picture of the motivation behind behaviors, the authors of this study chose the TRA model to describe the relationships between desired variables. Specifically, future research should capture and test how subjective norms influence the relationships outlined here. It is important to note that PT students will likely be exposed to 2 sets of subjective norms: (1) Those espoused by their entry-level degree program, and (2) those espoused by their clinical practice partners. Exploring the differential impacts of these norms may provide further insight into the development of next generation physical therapists. Fourth, the authors provided study participants with descriptions of both MPH and SPH (with pictures of each performing a sit-to-stand transfer requiring moderate assistance) as a means to standardize participant interpretation of survey items. This attempt to ensure objectivity and uniformity of participant response may not have eliminated subjective interpretations of survey items, such as amount of assistance specified or necessity for SPH practices. Additionally, we recognize that not all student PT participants shared similar clinical experiences, particularly those that would have required SPH during their supervised clinical practice.
Finally, the construction and use of the survey instrument targeted student PT perception of future use of SPH. Thus, participant response may not have reflected actual behavior while completing clinical affiliations in settings where patient handling tasks are common. The study was cross-sectional over a brief period at the end of a semester and did not follow participating student PTs beyond their graduation and entrance into professional practice. Knowing this, the question of whether entry-level graduates would persist in their attitude or behaviors regarding advocacy for SPH could not be answered. Future research using a more longitudinal design would be helpful to identify whether SPH behaviors and leadership expectations for advocacy transfer to clinical practice following graduation. Further research also might address different forms of patient handling education in entry-level physical therapist education programs, such as online instruction, equipment demonstrations from vendors, and evaluation of PT-driven models of SPH programs in practice.
Didactic education (classroom and laboratory) appears to have a significant impact on the attitudes and intentions of entry-level students, driving future behaviors related to patient handling tasks involving lifting and transfers. Physical therapist education programs that include SPH education and evidence of injury prevention for patient handling tasks may help promote the adoption of SPH practice for the profession by fostering leadership that promotes SPH support and advocacy among program graduates. The results of our study show that both didactic and clinical education appear to have an impact on student leadership intentions with regard to SPH and that this relationship is mediated by student attitudes toward SPH. In short, teachers influence student attitudes that then persist beyond the classroom. Future studies featuring longitudinal follow-ups may highlight the importance of SPH educational objectives as a means to transform the culture of physical therapy practice from manual patient handling to SPH.
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