2.1. Study design, setting, and participants
This cross-sectional study was done between August and December 2019 in the two cities of Iran and in the educational hospitals of these cities. In coordination with the nursing team, participants were enrolled from the nurses and other patient handlers. A sample of 350 patient handlers was participated from these hospitals. Patient handlers whom they didn't accept defined procedures were excluded from the study. The inclusion criterion included all patient handlers who have done patient handling for minimum 1 year. From all, 249 participants were remaining to the end of the research.
2.2. The Original instruments
2.2.1. Nurses’ Attitudes Regarding the Safe Handling of Patients Who Are Morbidly Obese
This questionnaire includes 26 questions with 5 point likert (strongly agree to strangle disagree). Also a set of demographic questions were answered by patient handlers. In the first part of it, the definitions of super heavy and obese patient were stated and six of 26 items, were asked about obesity itself (ex, I believe obesity is due to lack of self-control). The content validity index and test-retest reliability score were reported as satisfactory by authors. As stated by authors the final 26 items were classified in nine subscales including: Nurses’ perception of stress/ demands of handling patients who are morbidly obese, Nurses’ perception of controllable factors of obesity, Nurses’ motivation to use safe handling equipment with patients who are morbidly obese, Nurses’ perception of time/ workload involved in SPH of patients who are morbidly obese, Nurses’ perception of nursing peers’ responses to patients who are morbidly obese, Nurses’ perceived confidence in assessing safe handling needs of patients who are morbidly obese, Nurses’ perception of safety as a priority, Nurses’ perception of uncontrollable factors of obesity, Nurse’s own response to patients who are morbidly obese (19).
2.2.2. Safe Patient Handling Perception Scale
This tool was introduced by the team of researchers affiliated to U.S.A. The aim of this 17-item questionnaire was to assessing perceptual risk of musculoskeletal disorder in the healthcare context. Seventeen items are grouped into 3 themes according to factor structure analysis: knowledge (11 item), practice (3 item), and resource accessibility (3 item). Alpha score was reported for each subscale which was 0.886, 0.901 and 0.855 for knowledge, practice and accessibility subscales, respectively. The authors stated that this measure can be used to assess employee perceptions of Safe Patient Handling policies and practices. The 5 point likert scoring method was used to gathering the data (20).
2.3. Translation procedure
As recommended by literature, linguistic validation technique was used. Translation from English to Persian was done by two bilingual expert translators. An agreement between researchers and translators was calculated for Persian version of two questionnaires. Then one translator with academic background in the healthcare Ergonomics domain, who was blinded to the original version, translated the Persian version back into English. The content of the English version produced by the research team was endorsed in several correspondences with the main authors (19, 20). The aim of this step was to ensure that the content is identical to the original. The original and back-translated versions were checked item by item in coordination of translators and main researchers. As a consequence of these meetings, the final Persian versions of two questionnaires were prepared.
2.4. Reliability assessment
Reliability of the translated version was assessed by Cronbach's alpha coefficient which estimates the internal consistency of the tools. This procedure was calculated based on item-total correlation and estimate of alpha when an item was removed from the scale. If 70% of the variance of the observed score was systematic, and the left 30% was due to random errors, the alpha was reported as 70% and considered acceptable.
2.5. Validity assessment
Validity testing for the two scales was based on content validity index/ratio analysis. An expert panel consisting of nurses and other caregivers that doing patient handling tasks (5) and Occupational Ergonomists (5) were participated in this stage. The Lawshi's method for analysis of Content Validity Ratio (CVR) was used in the present study. Responses of experts for each item were divided into three categories, including: "necessary", "useful, but unnecessary" and "Unnecessary". The CVR calculated according to completed questionnaires as depicted below:
ne: number of persons responding to requested questions
N: total number of experts
Simplicity, relevancy and clarity were considered by experts separately to be scored in evaluating the CVI in a Likert scale Simplicity, relevancy and clarity were considered by experts separately to be scored in evaluating the CVI in a Likert scale.
2.6. Data analysis
Descriptive analyses were carried out to describe the patient handlers’ characteristics. Kolmogorov–Smirnov was used to assess normal distribution of data. After checking the CVR and CVI, for testing the validity of instruments, an Exploratory Factor Analysis was run to extract latent factors. The standard Eigenvalue greater than one and scree plot was used to specify the number of extracted factors. For testing reliability of instruments, Cronbach’s alpha, a measure of internal consistency, was calculated for each sub-component. Kruskal-Wallis Test or Mann–Whitney U was used. Analyses were conducted by SPSS. A significance level of 0.05 was utilized for testing the hypothesis.
2.7. Ethical approval
This study was approved by the ethical committee of Hamadan University of Medical Sciences (Reference: 980210777). The nursing management of each ward was also approved the procedure. Written consent was obtained from all of 249 patient handlers.