Development and Pilot Testing of the Cutaneous Lupus Screening Tool.

Importance: Patients with cutaneous lupus erythematosus (CLE) experience significant morbidity and poor quality of life. In the absence of a dermatologist's examination, no reliable tool exists to confirm whether a patient has CLE for use in epidemiologic studies.

Objective: To determine whether the Cutaneous Lupus Screening (CLUSE) tool can detect cases of CLE by measuring its performance in individuals with dermatologist-diagnosed CLE compared with individuals without CLE.

Design, Setting, And Participants: The CLUSE tool is a novel, self-administered questionnaire with 15 closed-ended questions derived from the Delphi method. It includes features of disease validation for CLE as well as its most common phenotypes. This pilot study was administered during a 1-year period (July 1, 2011, to June 30, 2012) in outpatient dermatology clinics at an academic medical center. Data analysis was performed July 1, 2012, to November 30, 2013. Participants were individuals 18 years or older who had a definitive diagnosis of CLE or any other non-CLE dermatologic condition as established by a board-certified dermatologist. Eligible patients were recruited consecutively, and no individual approached declined to participate.

Main Outcomes And Measures: Sensitivity and specificity of the individual questions from the CLUSE tool in predicting CLE, comparisons between summary scores for the dichotomous questions between the CLE cases and non-CLE controls, and 9 scoring algorithms that assign a diagnosis of CLE and its subtypes depending on an individual's response to each question.

Results: A total of 133 patients were given the CLUSE tool; 16 participants were excluded. Responses from 117 individuals were collected for analysis and included 24 CLE cases and 93 non-CLE cases. In the 117 questionnaires analyzed, mean (SD) and median (interquartile range) CLUSE scores differed in the CLE (5.6 [2.1] and 5.5 [3-10], respectively) vs non-CLE (0.96 [1.6] and 0 [0-7], respectively) groups (all P < .001). Of the 9 algorithms, algorithm 9, used for diagnosing CLE regardless of subtype, demonstrated the highest sensitivity (87.5%) and high specificity (96.8%).

Conclusions And Relevance: A combination of questions and representative photographs can ascertain cases of CLE with high sensitivity and specificity. The CLUSE tool is a brief, self-administered questionnaire with low respondent burden used for the identification of CLE. In the future, this questionnaire will be administered to large, established patient databases to gather epidemiologic data on this disease.