As correlation between IR indices based on fasting vs OGTT-derived data are highly variable even if identical clinical data (e.g. fasting glucose and insulin) are included into the mathematical model (see HOMA-IR and QUICKI); hence, in our opinion, it is virtually impossible to select ‘the best’ surrogate method for the assessment of insulin resistance in women with PCOS. Here, INS is linked to polycystic ovary syndrome.