Development and validation of the Occupational Back Pain Prevention Behaviors Questionnaire in nursing personnel

Background: Occupational back pain is the most prevalent health problem among nurses that needs to be assessed by a valid and multi-factorial questionnaire. The purpose of the present study was to design and develop an instrument for assessing job-related back pain prevention behaviors among nursing professionals. Methods: First an item pool of 49 items was generated. Then, content and face validity was carried out. Consequently, a cross-sectional study was conducted in Mazandaran, Iran. The questionnaire was distributed among a sample of nurses working in hospitals affiliated to Mazandaran University of Medical Sciences. Exploratory factor analysis was used to determine the factor structure of the questionnaire. Item-scale correlation matrix employed to examine the construct validity. The Cronbach’s alpha was estimated to assess the reliability and the intraclass correlation coefficient was calculated to examine stability. Results: In all 155 nurses participated in the study. The mean age of respondents was 34.1 (SD = 7.66) years, and 83.2% were female. Six factors with 30 items emerged from the exploratory factor analysis: knowledge, attitude, self-efficacy, reinforcing factors, enabling factors and behavior that jointly accounted for %66.5 of variance observed. Item-scale correlation matrix showed satisfactory results lending support to construct validity of the questionnaire. The Cronbach’s alpha coefficient showed excellent internal consistency (alpha=0.92). The intraclass correlation coefficient with 2-weeks interval also indicated that the questionnaire has satisfactory stability (ICC = 0.97). Conclusions: The findings showed that the Occupational Back Pain Prevention Behavior Questionnaire is a reliable and valid instrument for measuring occupational back pain prevention behaviors among nurses.


Background
Low back pain is considered a major health problem worldwide. It leads to disability, absenteeism and considerable annual health costs (1). One major risk factor of low back pain is what people do as their professional job. Among professional jobs, nursing professions are experiencing higher risk of low back pain compared to other jobs, and it accounts for 60% of the reported occupational injuries among this population (2)(3)(4). Thus any interventions to promote preventive low back pain behaviors among nurses are worthwhile. In addition, any attempts to understand and measure preventive behaviors among nurses could be of prime importance.
There are a number of questionnaires that designed to understand how much low back pain affects one's ability to manage routine activities. For instance, the Quebec Back Pain Disability Scale, the Roland-Morris Disability Questionnaire, the Oswestry Low Back Pain Questionnaire, and the Short-Form McGill Pain Questionnaire-2 that are just to name a few (5)(6)(7)(8). However, these questionnaires do not examine the cause of pain and behaviors, which leads to back pain. Thus, for development of any intervention to tackle job-related back pain among different professions we need to understand main causes of low back pain in the first place, and secondly, since the pain usually originates from behaviors during work-related activities it should be, to some extent, within a realm of educational planning models.
The PRECEDE-PROCEED model is the most popular and commonly used framework for health education planning programs. This model identifies behavioral, environmental, educational and ecological factors that are contributing to a problem (9). It is believed that a behavior can be influenced by predisposing, reinforcing, and enabling factors and thus a program based on the PRECEDE-PROCEED model seeks to identify these three factors. The predisposing factors include knowledge, attitudes, beliefs, values, and self-efficacy. The reinforcing factors include attitudes and behaviors among those who are involved, and enabling factors include access to resources, availability of health services, policies, legislation, and existing regulations, and behavioral skills that are affecting the adoption of a health behavior (9). Thus, as part of a study to develop an intervention for reducing low back pain in nursing personnel, the purpose of this study was to design an instrument based on the PRECEDE-PROCEED model.

Item generation
The initial questionnaire was developed through semi-structured interviews with nursing professionals. Participants were asked to explain about job-related low back pain and indicate the ways that could prevent low back pain in nursing personnel. The interviews were carried out by one of us (SSK) individually in the office of participants or the nursing office and in a quiet environment. Interviews continued until data saturation was achieved. As such 18 nurses, head nurses, educational supervisors, nursing managers, hospital managers, hospital affairs experts, quality improvement experts, and development and support managers were interviewed. For further certainty, two more interviews were conducted, but no new data was obtained. Accordingly, based on the interviews and literature review, the preliminary questionnaire containing 49 items was developed. Then the research team assessed the questionnaire and 9 items were deleted to ensure the clarity, objectivity and the ease of comprehension of the terms employed.
Thus at this stage in all 38 items was remained.

Developing a preliminary questionnaire
At this stage, we assessed content and face validity. To determine the content validity, qualitative and quantitative methods were used (10). For qualitative content validity 10 experts in health education, physiotherapy, educational management, and nursing were asked to check the quality of the questionnaire based on grammar, use of proper words, item allocation and scaling. Then the content validity ratio (CVR) and content validity index (CVI) was used to evaluate quantitative content validity. To determine the content validity ratio, the questionnaire was sent to 10 experts with different specialty (including health education, physiotherapy, nursing, education management) and was asked to respond where the items are essential, useful but not essential and no essential. Then responses were calculated based on the formula and matched to the Lawshe's table (11).
The same experts were asked to indicate whether items are simple, relevant and clear in order to calculate content validity index (12,13). The CVR for the questionnaire was 0.84, which was well above the recommended value. The CVI for the questionnaire was 0.98.
However, at this stage, 7 items were removed and the number of items was reduced to 31.
Similarly, for face validity, qualitative and quantitative methods were used. The qualitative face validity determined by asking 10 nurses (the potential user of the questionnaire) to complete the questionnaire and to indicate whether any items were difficult, ambiguous or irrelevant. In the next step, Item Impact Score was calculated in order to assess the importance of each item by the same nurses. For each item, a 5-point Likert response category was considered: strongly important, quite a lot important, moderately important, slightly important and not at all. The analysis showed that the impact score for all items was above 1.5 (the actual mean impact score was 3.73). There were no additional changes at this stage and thus the provisional version of the questionnaire with 31 items was subjected to psychometric evaluation.

Psychometric evaluation
A cross-sectional study was conducted to examine the psychometric properties of the questionnaire. The questionnaire was administered to a sample of nursing personnel recruited from teaching hospitals affiliated to Mazandaran University of Medical Sciences, Sari, Iran. Indeed, first we provided a list of all hospitals and three hospitals were randomly selected. Then in each hospital, individuals randomly selected based on a simple random number table and staff identification (ID).

Statistical analysis
To assess construct validity, the exploratory factor analysis and item-scale correlation matrix were employed. Indeed, the Kaiser-Meyer-Olkin (KMO) Index and Bartlett's Test of sphericity were used to assess sampling adequacy (14). The factor structure of the questionnaire was extracted using Varimax rotation. The presence of an item in a factor was determined as approximately 0.4 as recommended (15). For item-scale correlation matrix, the Pearson correlation coefficient was used and coefficient values of 0.4 or above were considered acceptable (15). The reliability of the questionnaire was assessed using internal consistency and stability. To compute the internal consistency, the Cronbach's alpha coefficient was estimated. To demonstrate the stability of the questionnaire the Intraclass Correlation Coefficient (ICC) was calculated. For this purpose, a subsample of 20 nurses completed the questionnaire twice with a two-week interval.

The sample characteristics
In all, 155 nurses aged 24 to 55 years participated in the study. The mean age of respondents was 34.1 (SD = 7.66) years, and 83.2% were female. Participants were nurse, head nurse and educational supervisors from different units. The mean work experience of participants was 9.81 (SD = 7.0) years. The characteristics of participants are shown in Table 1.

Item-scale correlation matrix
The correlation between items and their own subscales are presented in Table 3. As expected items belonging to a given factor showed a significantly higher correlation with its own subscale compared to other subscales.

Reliability
The Cronbach's (alpha) coefficient for the entire scale was 0.92 and ranged from 0.49 to 0.87 for various domains. The intraclass correlation coefficient (ICC = 0.97) also indicated that the questionnaire has satisfactory stability (Table 4).

Discussion
The purpose of this study was to design and psychometrically appraise an instrument to measure occupational low back pain preventive behaviors among nurses. The initial items were originated and developed based on data from a qualitative study and review of the literature on studies of job-related low back pain in nursing personnel (16)(17)(18)(19). In generating the statements we also considered the biopsychosocial characteristics for low back pain among the nursing professionals. It is argued that individuals, who experienced a problem, are the best ones to provide input on factors, which might be effective in imitation of a condition (20). In fact we have tried to ask nurses about factors, which might affect their low back pain in the framework of the PRECEDE-PROCEED model.
Interestingly most participants completed the questionnaire without any hardness since they received it user-friendly.
There are two concepts of enabling factors and administrative policy diagnosis in the PRECEDE-PROCEED model. They refer to characteristics of the environment that assist the action and any skills or resources require to achieve specific behavior. Also, this could hamper or facilitate the development of a health program (9,21). In the present study, both concepts were grouped into one category and named 'enabling factors'. Green and Kreuter believe these are important items and can lead to a behavior change (9).

Ethics approval and consent to participate
The Ethics Committee of Tarbiat Modares University approved the study. Informed consent was obtained from all participants.

Consent to publish
Not applicable.

Availability of data and materials
The datasets used and/or analyzed during the current study are available from the corresponding authors on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Funding
The study funded by Tarbiat Modares University.

Authors' Contributions
SSK was the main investigator, collected and analyzed the data, and wrote the first draft.
SST supervised the study and contributed to writing process. AH helped in design and contributed to writing process. AM was the study advisor, contributed to analysis and interpretation, and provided the final draft. All authors read and approved the final manuscript.

21.
Ottoson JM, Green LW. Public health education and health promotion. Public Health