Application of the theory of planned behaviour to explain adult male anabolic androgenic steroid use among gym users

Background and aims: In the UK, the illegal use of anabolic androgenic steroids (steroids) among recreational gym-users has been increasing alongside a growth in the number of steroid-users accessing harm reduction services. Steroid-misuse has therefore become a public health concern. This study explored first-hand experiences of steroid-users’ attitudes towards and motivations for using steroids. It also explored whether and how societal and individual pressures as well as barriers and facilitators influence steroid-users’ decisions to use steroids. One key aim was to develop a Theory of Planned Behaviour (TPB; Ajzen, 1988; 1991) questionnaire. This study also examined the application of TPB variables (attitudes, subjective norms, perceived-behavioural-control and their respective underlying beliefs) to account for the variations in intention to use steroids. Finally, the study explored the differences between steroid-users and non-steroid-users in terms of the TPB variables (i.e., differences in explanation of actual past or current behaviour, and predictions of future intentions within a steroid-user group), as well as their underlying beliefs towards steroids. Methodology: This study used a cross-sectional mixed methodology (exploratory sequential design). The study utilised the TPB theoretical framework and consisted of two phases: (I) A qualitative exploration of steroid-use, leading to the development of a TPB questionnaire and (II) The use of the developed TPB questionnaire to investigate participants’ future intentions concerning steroid-use or non-use.188 adult male recreational gym-users (113 steroid-users and 75 non-steroid-users) participated in this study. Participants were recruited from various online social media (e.g., Facebook, bodybuilding forums) and from Addaction within Lincolnshire, where paper copies of the questionnaire were available. Results: Findings from phase one led to the development of the TPB questionnaire as well as providing novel insights to explain reasons for steroid-use (e.g., reduced natural testosterone levels, self-protection) accounted for outside the TPB framework. During phase two, hierarchical multiple regression revealed that a positive attitude towards steroid-use among users is the most 3 important contributing factor for explaining future intentions to use the drug. Findings from the two individual logistic regressions and between group comparisons highlighted that steroid-users’ attitudes towards steroid-use and perceived-behavioural-control (i.e., a higher level of positive control and factors that enabled steroid-use) were higher than non-users. Non-users’ normative beliefs (i.e., a perceived increase in negative social pressure and disapproval from significant others) were higher than users. Conversely, users perceived a positive outcome of steroid-use whereas non-steroid-users perceived an increased negative outcome of steroid-use for behavioural beliefs. Finally, independent t-tests identified particular beliefs and factors that the groups differed on (e.g., non-users mostly reported unfavourable consequences of steroid-use). Conclusions: This study provides evidence that the application of the TPB can be useful in understanding an individual’s future intentions concerning steroid-use or non-use. The TPB could be used in future research as a template for the development of harm reduction, awareness and education programmes. Furthermore, it may be applied within clinical practice by supporting healthcare professionals to develop specific interventions to target the TPB variables in order to help reduce the use of the drug