Purpose Amid a political agenda for patient-centred healthcare, shared decision-making is reported to substantially improve patient experience, adherence to treatment and health outcomes. However, observational studies have shown that shared decision-making is rarely implemented in practice. The purpose of this study was to measure the prevalence of shared decision-making in clinical encounters involving physiotherapists and patients with back pain.Method Eighty outpatient encounters (comprising 40 h of data) were observed audio-recorded, transcribed verbatim and analysed using the 12-item OPTION scale. The higher the score, the greater is the shared decision-making competency of the clinicians. Results The mean OPTION score was 24.0 % (range 10.4-43.8 %). Conclusion Shared decision-making was under-developed in the observed back pain consultations. Clinicians' strong desire to treat acted as a barrier to shared decisionmaking and further work should focus on when and how it can be implemented.