AbstractOBJECTIVE: To examine if physiotherapists treating patients with PFP can predict the effect of a 12-week training intervention measured on function based on an initial assessment.STUDY DESIGN: Secondary analysis of a randomized trial comparing quadriceps exercises with hip exercises in patients with patellofemoral pain as is two independent cohort studies that analyze the association between physiotherapists’ prognosis and function and TransQ.METHODS: Physiotherapists were asked to predict the prognosis of a total of 200 PFP patients on a 0-10 scale. Outcome measures consisted of changes from baseline to 12 and 26-weeks on the KUJALA questionnaire and dichotomized TransQ. Linear and logistic regression analyses were performed to assess the prediction of KUJALA and TransQ. RESULTS: No association was found between physiotherapists’ assessment of prognosis and changes in function using KUJALA for either QE or HE at 12 and 26-weeks (Slope = -0.39 to -0.46 with wide CIs). No association was found between physiotherapists’ assessment of prognosis using TransQ for either QE or HE at 12 and 26 weeks (OR = 1.05 to 1.19 with wide CIs). The physiotherapists used previously validated prognostic factors such as symptom duration and pain intensity in their reason for prediction.CONCLUSION: Physiotherapists’ prediction of the prognosis is not associated with changes in function or treatment success based on initial assessment after 12 and 26-weeks for patients with PFP, despite using previously validated prognostic factors. Physiotherapists’ prognoses are not useful as an additional source of information in decision-making and identifying patients with poor projected outcomes.