PURPOSE: To determine whether the Asthma Control Questionnaire (ACQ) is a more reliable measure of asthma control than the Asthma Control Diary (ACD)among symptomatic asthma patients.
METHODS: This a descriptive cross-sectional study involving 35 patients at the out-patient department. Each subject filled up two sets of diaries for one week each diary, and two sets of questionnaires, each given at the seventh day of the diary. We measured reliability of both the questionnaire and the diary using the paired t-test, retest reliability and alpha reliability.
RESULTS: Absolute scores were consistently higher for the questionnaire than for the diary at the end of week one and week three. Correlations between the questionnaire and the diary were significant. The overall concordance or agreement between the two was high (ICC of 0.83 for Week 1 and ICC of 0.82 for Week 3). The within-sample variation for the questionnaire and diary were 0.14 and 0.18, respectively. These resulted in the questionnaire having better reliability (ICC=0.82) than the diary (ICC=0.65). The alpha reliability was also higher for the questionnaire (0.90) than the diary (0.79) indicating a stronger internal consistency between the mean of the items for the questionnaire than for the diary.
CONCLUSION: Tests for reliability tended to be better for the questionnaire than for the diary. If one weighs the advantages and disadvantages of a diary versus a questionnaire for measuring asthma control, the advantages of the questionnaire outweigh those of a diary. It can therefore be used in the general outpatient clinics.
CLINICAL IMPLICATIONS: This study shows that answers elicited by the physician is still better compared to the patients recording their own symptoms in assessing control in symptomatic asthma patients. However, these clinical instruments still cannot replace the objective findings obtained in peak flow meter or spirometry in settings where it is readily available.
DISCLOSURE: Judith Sanico-Soliano, No Financial Disclosure Information; No Product/Research Disclosure Information