Comparison of Self-reported Versus Actual Height and Weight in the Orthopaedic Population

The purpose of our study was to determine the accuracy of orthopaedic patient’s reported height, weight, and body mass index (BMI). We hypothesized that patient’s age, sex and/or BMI may affect their accuracy. We performed a prospective, observational study in the setting of our orthopaedic clinic. Differences between self-reported and actual values were calculated. Patients were categorized based on their age (< 65 vs. ≥ 65), sex, and actual BMI (<30 vs. >30). Student t-test and chi-square test were used to compare groups. Our study included 329 patients. Patients were more likely to underestimate weight (p < 0.001) and overestimate height (p = 0.007). Comparing patients with a BMI < 30 and > 30, height overestimation (0cm vs. 1.14cm, p = 0.004) and weight underestimation (0.09kg vs. 1.29kg, p = 0.02) discrepancies were greater in the BMI > 30 group. Patients, particularly with a BMI >30 kg/m2, over-estimate their height and under-estimate their weight. (Journal of Surgical Orthopaedic Advances 30(3):176–180, 2021)

Key words: total joint arthroplasty, total knee arthroplasty, total hip arthroplasty, practice management, body mass index, patient reported data