RT Journal Article
SR Electronic
T1 Validity and reliability evidence of the nijmegen questionnaire in astma
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P1307
VO 42
IS Suppl 57
A1 Eirini Grammatopoulou
A1 Emmanouil Scordilis
A1 Afrodite Evangelodimou
A1 Aikaterini Haniotou
A1 Arietta Spinou
A1 Nikolaos Tsamis
A1 Konstantinos Grigoriadis
A1 Dafni Antoniadou
A1 Maria Xyki
A1 Vlassia Belibassaki
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P1307.abstract
AB IntroductionThe Nijmegen Questionnaire (NQ) is the most commonly used screening tool for hyperventilation. The validity of the NQ has not been reported for Greek asthma out-patients.AimReport the validity evidence of the Nijmegen Questionnaire in asthma.Methods162 Greek asthma out-patients (86 with mild and 76 moderate asthma) participated in the study. Hyperventilation was assessed using NQ and clinical measures such as breath holding time (BHT), respiratory rate (RR) and end-tidal CO2 (ETCO2). Construct validity was tested through factor analysis and cross-sectional validity through correlations of the NQ score with BHT, ETCO2 and RR (Pearson’s r correlation coefficient).ResultsExploratory factor analysis for the three pre-hypothesized factors of the 16 item NQ showed low factor loadings which led to a principal component analysis (PCA) for NQ. The PCA revealed a one-factor solution with 11 items (Q1, Q2, Q4, Q5, Q6, Q7, Q8, Q9, Q11, Q13, and Q16). The one-factor solution revealed a total of 58.86% of explained variability and a high Cronbach alpha (a = .92). These findings were supported by confirmatory factor analysis for the 11 items NQ model [χ2 = 149.90, df 44, p<.01, χ2 /df ratio = 3.407, CFI = .99, IFI = .99, AGFI = .98, SRMR = .14, RMSEA = .14.]. Cross-sectional validity testing showed moderate correlations of the NQ score with ETCO2 (r = -.77, p< .001), RR (r = .66, p< .001), BHT (r = -.65, p< .001).ConclusionThe NQ was valid and reliable in the present sample with asthma.View this table:Loadings and communalities of the 11 item NQ model