The Predictive validity and effects of using transtheoretical model to increase physical activity of health workers at Dr. George Mukhari Hospital, South Africa

Abstract

Background: Evidence exists that supports the physiological and psychological benefits associated with regular physical activity. The Transtheoretical model (TTM) of the stages and processes of change has been used worldwide to understand how people change problem behaviour, such as Physical Inactivity, and correctly categorize people according to their readiness to change from being physically inactive to being active. This model (TTM) helps Health Promoters to implement awareness campaigns according to individual’s stage of exercise change. The overall aim of this study is to determine the predictive validity and effects of using Transtheoretical model to increase physical activity of health workers at Dr. George Mukhari Hospital in South Africa. Methods: Research design: A quasi-experimental design was used. A total of 200 subjects (both medical and non-medical staff) were randomly selected from the hospital staff. The following parameters were measured at baseline: TTM Stage (Questionnaire), fitness levels (step test), BMI (Electronic scale), attitude and knowledge (Questionnaire). Phase 11: impact evaluation; exposure levels; Phase 111: Knowledge; Attitude; TTM post intervention. The results were analyzed using SPSS 17.0 version and excel programs. Chi square test was used to analyse and calculate the p-value scores. Paired Sample t-test was used to compare means and binomial and multiple logistic regressions were used to calculate predictive validity of TTM. Results: Two hundred staff members with mean age of 43.12 and standard deviation of 10.75 were investigated. Baseline results showed that the majority of the participants were at Pre-Action stage (76%) and only 24% were at Action stage; with only 27% who had Normal weight and 73% Overweight and Obese. NCDs are common in many participants, with obese ones being more affected than normal staff. Nonmedical staff had poor knowledge compared to medical staff (p<.05). Majority of staff generally had positive attitude towards PA. There was a significant difference (p<.050) between males and females in each TTM stage, with more adult males being in Action/maintenance stages compared to adult females who were mainly at pre-action stages. Majority of older patients were obese (p<.05), had a good perception about their weight and at pre-action stages. Post intervention, Mean scores of TTM (3.699) and Knowledge (3.651) were significantly (p<.05) higher at post test. Both medical and nonmedical staff mainly used Environmental re-evaluation and Self re-evaluation as processes of behaviour change. Precontemplators only used 2 processes to change behaviour. Post intervention: high levels of exposure; Processes of Change, knowledge and attitude resulted in increased TTM stages of staff (p=.000). TTM, knowledge, attitude, process of change and level of exposure were used as predictors of behaviour change and significantly predicted success post test. Overall accuracies of TTM at pre-test could be classified correctly of TTM at post test by average 66.9 % for overall participants; 78.3% for medical staff and only 65% for non-medical staff. Thus the predictor (TTM1) had significant contribution to the outcome (TTM2).

Conclusion: Obesity is a common problem and is predisposed by physical inactivity because the majority of staff is old, and this puts them at risk of inactivity-related chronic diseases of lifestyle. Level of physical activity was significantly associated with BMI and may be one of the most important risk factors associated with obesity among hospital staff. The use of TTM to identify the stage of PA of healthcare workers (HCW) has enabled the researcher to design intervention programs specific to the stage of exercise behaviour of staff. Thus the predictors (TTM1), exposure levels, knowledge, attitude and Processes of change have significant contribution to the outcome (TTM2).