OBJECTIVES: Polycystic ovary syndrome (PCOS) is one of the most common female endocrine disorders. It presents with a broad range of symptoms and has significant and diverse clinical implications. In order to develop a comprehensive understanding of PCOS, a (conceptual) disease model was developed. METHODS: The disease model was generated based on three lines of concept evaluation research; (1) a targeted literature review, (2) interviews with clinical experts; (3) concept elicitation interviews with patients, for which data was recorded, transcribed and coded. Collectively, this provided a comprehensive list of the sign, symptom and impact concepts most important and relevant to women with PCOS. RESULTS: Nineteen peer-reviewed articles were included in the literature review. Five clinical experts (USA, Turkey, Netherlands) and 20 PCOS patients (mean (SD) age 29.2 (5.9) years) were included in 1:1 qualitative interviews. Concept saturation was observed in patient interviews.  Significant overlap was seen in the sign, symptom and impact concepts of PCOS across the three lines of evidence. Signs/symptoms were categorized into pain, infertility, hirsutism, alopecia, acne, menstruation (e.g. irregular menstruation, heavy bleeding), bloating, weight-related (e.g. weight gain, fluctuations), and metabolic abnormality (i.e., obesity, difficulty with weight loss, etc) symptoms. Some symptoms, such as pain at non-menstrual times, were uniquely reported by patients. Impacts of PCOS included sleep disturbance, emotional functioning, social role functioning and physical functioning. Compensatory behaviours (e.g. hair removal, diet changes, use of medication) were common. The relationship between these concepts is presented in a disease model. CONCLUSIONS: This is the first known comprehensive disease model for PCOS. It shows many of the defining features of the condition can only be accurately and reliably captured by asking patients how they feel and function. This work underscores the need for measurement of PCOS from the patient perspective using a patient reported outcome (PRO).