Objective: To determine the accuracy of recalled height and weight, and calculated body mass index (BMI), over a 27-37 y period.
Design: Comparison of measured height and weight with recalled height and weight 27-37 y later.
Participants: Two hundred and twenty-five men measured aged 18-24 y as physical education students at Loughborough Training College, UK, between 1958 and 1967.
Results: Initial body weights were over-estimated by 3.1 +/- 4.5 kg and heights by 1.1 +/- 1.8 cm, on average. Some 42% (95) of recalls were within 2.5 kg and 79% (178) within 2.5 cm, resulting in 58% (130) of the differences in BMI calculated from recalled and actual heights and weights to be within 1 kg/m2. However, 29% (66) of recalls were more than 5 kg and 8% (19) more than 10 kg from the measured values. Weight errors (actual-recalled) were negatively related (r = -0.43, P < 0.001) to weight gain over the 27-37 y interval.
Conclusions: Middle-aged men who were formerly physical education students recalled their previous height and weight well, in most cases, 27-37 y later. The bias from recalled data would be to underestimate weight gain by 3 kg and BMI by 1 kg/m2, on average. Errors of more than 5 kg in 29% of participants and of more than 10 kg in 8% would be expected to interfere seriously with attempts to show epidemiological relations between early weight based on recall and subsequent outcomes.