Validation of alternate modes of administration of the lung function questionnaire (LFQ) in subjects with smoking history
Purpose: The Lung Function Questionnaire (LFQ) was developed and validated as a case-finding tool to identify patients at risk of airflow obstruction (AO) that should be evaluated further using spirometry. Our objective was to assess the usability and validity of additional questionnaire-administration modes, including Web-based, interactive voice response system (IVRS)-based, and interviewer-based modes.
Design: This multicenter, prospective, noninterventional data-collection study enrolled 149 individuals aged ?40 years with current or former smoking history. A two-visit crossover design was employed; patients completed the paper-based LFQ and were randomly assigned to complete one of three alternate modes.
Methods: Statistical evaluation included item-level, scale-level, and AO risk-classification comparisons; a satisfaction survey assessed patient preference.
Results: This study showed a great degree of concordance between alternate forms of the LFQ and the paper version. Results indicated an absence of floor and ceiling effects and the average LFQ item-level means were consistent across modes. LFQ scores were stable between assessments, (administered approximately one week apart) showed exceptionally good agreement, and AO risk classification using the LFQ cut point was consistent across modes.
Conclusions: The LFQ is an important case-finding tool to aid primary care physicians in further evaluating symptomatic patients at risk of AO. The alternate modes will further facilitate the implementation and widespread uptake of this tool.