[Validation of the Spanish version of the Chronic Obstructive Pulmonary Disease-Population Screener (COPD-PS). Its usefulness and that of FEV₁/FEV₆ for the diagnosis of COPD].
OBJECTIVE
The chronic obstructive pulmonary disease (COPD) is a highly undiagnosed disease. The use of short screening questionnaires designed to detect chronic airflow obstruction may help to the early diagnosis of COPD.


METHODS
This was an observational, cross-sectional epidemiological study aimed to validate the translated into Spanish version of the COPD-PS questionnaire. Socio-demographic and clinical data of participants were collected, as well as their answers to the COPD-PS and EQ-5D questionnaires. The ratio FEV(1)/FEV(6) was measured with the COPD-6 device. The psychometric properties of the questionnaire and the diagnostic yield of the FEV(1)/FEV(6) ratio were analysed, both referred to the gold standard of post-bronchodilator FEV(1)/FVC < 0.7.


RESULTS
Ten primary care centers participated in the study and included 94 controls and 79 cases with chronic airflow obstruction. Questionnaire characteristics were: feasibility, 2.3% of participants did not answer at least one item; mean time to fill the questionnaire was 47.7 seconds; 4.7% of individuals had a 0 score. Validity, moderate correlation with EQ-5D scores and moderate-high with FEV(1); the scores of COPD-PS were related to all parameters associated with COPD. A cut off of 4 units had the best sensitivity/specificity ratio and correctly classified 78% of participants. For the FEV(1)/FEV(6) ratio, a cut off of 0.75 correctly classified 85% of individuals.


CONCLUSIONS
The COPD-PS questionnaire demonstrated good psychometric properties. A cut off score of 4 has excellent predictive value. A ratio of 0.75 in the FEV(1)/FEV(6) provides an excellent correlation with the ratio FEV(1)/FVC and is useful for the identification of individuals with chronic airflow obstruction.
Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Ciber de Enfermedades Respiratorias (CIBERES), Hospital Clínic, Barcelona, España. marcm@separ.es
Marc
M
Miravitlles
Carles
C
Llor
Eduardo
E
Calvo
Silvia
S
Diaz
Helena
H
Díaz-Cuervo
Nuria
N
Gonzalez-Rojas
D000368:Aged; D000420:Albuterol / Q000494:pharmacology; D019540:Area Under Curve; D001993:Bronchodilator Agents / Q000494:pharmacology; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011594:Psychometrics; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis*; D015203:Reproducibility of Results; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012959:Socioeconomic Factors; D013030:Spain; D011795:Surveys and Questionnaires; D014175:Translating
D001993:Bronchodilator Agents; D000420:Albuterol