Validation of a Questionnaire for Assessing Adherence to Metered-Dose Inhaler Use in Asthmatic Children

Abstract

Maintenance therapies for asthma are vulnerable to low adherence. Clinicians would benefit from having a validated questionnaire to assess adherence to metered-dose inhaler use in children with asthma. The objective of this study was to design and validate a questionnaire assessing adherence to metered-dose inhaler use, to be filled out by the parents and/or caregivers of children with asthma. The six questions on the Pediatric Inhaler Adherence Questionnaire were obtained from reviewing the literature, from carrying out focus group discussions, and from the researchers' professional experience. We assessed concurrent criterion validity using canister weight change as the gold standard and also assessed test-retest reliability. The questionnaire was administered to the parents/caregivers of 64 children aged 3.6 ؎ 2.2 years. Questionnaire scores correlated positively with the absolute value of the difference between 100 and percent taken of prescribed (Spearman correlation coefficient rho ‫؍‬ 0.42, p ‫؍‬ 0.001). The sensitivity of the questionnaire in detecting nonadherent patients ranged from 50% to 75%; positive predictive value ranged from 23.1% to 66.7%; and likelihood ratio ranged from 1.5 to 5.5 for the detection of nonadherent patients. The Pediatric Inhaler Adherence Questionnaire is a valid, reliable, quick, inexpensive, and easy-to-use instrument that allows quantitative assessment of metered-dose inhaler adherence in children with asthma, and may be useful across a range of clinical and research settings. (Pediatr Asthma Allergy Immunol 2007; 20[4]:243-253.)

What are validated self-report adherence scales really measuring?: a systematic review

“…The timeframe specified ranged from 1 day to 12 months [9, 33 Thirty scales contained items that elicited information on barriers to, and determinants of adherence (groups 2, 3 and 5). Some of these adherence scales are disease-specific and thus explore common barriers that may influence adherence in these disease populations [48,49,56,60,61]. For example, the Pediatric Inhaler Adherence Questionnaire (PIAQ) explores adherence in patients with asthma and assesses the patient's difficulty in using asthma inhalers and the cost of inhalers [49].…”

“…Some of these adherence scales are disease-specific and thus explore common barriers that may influence adherence in these disease populations [48,49,56,60,61]. For example, the Pediatric Inhaler Adherence Questionnaire (PIAQ) explores adherence in patients with asthma and assesses the patient's difficulty in using asthma inhalers and the cost of inhalers [49]. Most of these adherence scales explore forgetfulness as a barrier to adherence and identify some of the situations where forgetfulness may be more common, such as when working or travelling [8, [62][63][64][65].…”

“…Most of these adherence scales explore forgetfulness as a barrier to adherence and identify some of the situations where forgetfulness may be more common, such as when working or travelling [8, [62][63][64][65]. Some adherence scales also explore physical barriers to adherence, such as vision problems, dexterity issues and dysphagia [40,49,66].…”

“…The time to complete the scale was reported in eight of the 43 adherence scales. Reported times varied from less than 5 min [49,56,58,68] to approximately 25 min (Table 2) [69]. The scales taking less than 5 min to complete consisted of 4 to 14 items.…”

Improving medication adherence in patients with chronic disease using a targeted and tailored approach

“…Most of these adherence scales measure the number of doses taken 12,42,181,[184][185][186]189,195,196,199,206,208 and contain items such as "how many days over the past month did you take less than prescribed? 181 " and "did you miss a tablet yesterday?…”