Validation of symptom‐based COPD questionnaires in Japanese subjects

Abstract

A simple self-administered questionnaire can help to diagnose COPD in Japanese subjects. When these questionnaires are used in Japan, cut-off values should be set somewhat higher than in Western countries.

Validation of the COPD Diagnostic Questionnaire in an Australian general practice cohort: a cross-sectional study

“…20,25 The ROCAUC in this study is less than two other external validation studies and less than the original study which had an ROC AUC of 0.816. 12,19,21 The ROCAUC in this study is closer to 0.5 than 1.0, where a test with an area under the curve of 1 would represent a perfect test with no overlap between true positives and false positives and the optimal operating point corresponding to the upper left-hand corner of the ROC graph ( Figure 2). 26 An ROCAUC of 0.5 indicates a test with no discriminative power and would be essentially worthless.…”

“…12,19,21 This is shown in Tables 2 and 3, with results of the other studies derived from their respective papers. 12,15,[19][20][21] Sensitivity and specificity at the cut-off point value of 16.5 (cutoff point A) were 79.7% and 46.8%, respectively and, at 19.5 (cutoff point B), the sensitivity and specificity were 63.0% and 70.1%, respectively. When compared with other validation studies (Table 3), sensitivity was lower at both cut-off points.…”

“…35%) is almost double the cases excluded from the CDQ validation study by Kotz et al 20 (18%) and substantially higher than the Greek and Australian external validity studies as well as the original study (9%). 12,19,21 This could be due to the different operators at each of the 36 sites for spirometry and the use of several different spirometry models, although every practice nurse received spirometric training. The other studies used independently trained operators such as respiratory physicians or research assistants to perform the spirometry and each study used one spirometer model/brand.…”

“…18 Although the CDQ was not developed as a diagnostic tool, it has been validated in comparison with spirometry in subjects selected from primary care settings in Europe and Australia and hospital outpatient clinics in Japan. 15,[19][20][21] Two of these studies investigated the validity of the Piko-6 ® flow meter (a form of microspirometry) as a screening tool for COPD diagnosis in primary care. 15,21 These studies also validated the CDQ and compared it with micro-spirometry.…”

“…21 The analysis methods were based on a protocol outlined by Price et al 12 The study measured the relationship between CDQ scores and COPD proportions determined by spirometry and these results were compared with the findings in the study by Price et al, one Australian and three international external validation studies. 12,15,[19][20][21] The variability in how the CDQ performed in this and other external validation studies was examined.…”