Figure 1.

Selection of patients with polycystic ovary syndrome (PCOS) and controls. A total of 14 417 129 patients were registered with 763 eligible practices during 2000 to 2017. Of these, 2 803 607 women were of 18 to 50 years old and were eligible. According to the criteria indicated in ‘methods’ section, there were 76 978 women with PCOS in PCOS cohort. The control cohort had 143 077 women who were matched within same general practice for age and BMI at a ratio of 1:2. There were 298 and 222 incident cases of sleep apnoea in PCOS and control cohorts respectively.