K.J. Yost, Department of Health Sciences Research, Mayo Clinic, 200 First St W, Rochester, MN 55905 (USA).
Patient-reported signs and symptoms are often the first indication of clinically relevant lymphedema.
Develop and assess the diagnostic accuracy of a screening questionnaire to detect lower extremity lymphedema (LEL) among normal weight and obese women.
Cross-sectional survey study.
We reviewed existing questionnaires assessing upper extremitylymphedema (UEL) for potential questions and worked with content experts to generate new items. A draft questionnaire with 59 items was reviewed by 5 physicians and 5 physical therapists specialized in lymphedema management and 5 female patients with clinically confirmed secondary LEL. A revised questionnaire with 45 items was administered by mail (n=186) or in a lymphedema clinic waiting area (n=28) to women with clinically confirmed LEL (cases, n=116) or UEL (controls, n=70). A parsimonious subset of items that best discriminated patients with and without LEL was identified using chi-square tests and logistic regression. Sensitivity and specificity for detecting LEL were estimated for the entire sample and for subsamples defined by obesity (BMI ≥30 versus < 30), which may confound the accurate diagnosis of LEL.
Questionnaires were completed by 127 women (LEL n=88; UEL n=39). A sum of 13 items (score range 0-52) was the most discriminating. Using a cutoff score of ≥5 points, the sensitivity and specificity for detecting LEL among all participants were 95.5% and 86.5%, respectively and 94.8% and 76.5% for obese participants.
By enumerating a sample with a high prevalence of LEL, we may have introduced spectrum bias, which may affect the accuracy of our screening questionnaire.
Our brief, 13-item self-report questionnaire is a sensitive and specific tool for detecting clinically relevant LEL among women, including those with BMI ≥30.