RESULTS: Study participants were using inhalers for a median of three years (interquartile range [IQR] 1-8 years). MDI and DPI (with both forms of devices manufactured in India) were being used by 115 and 85 asthmatics respectively. 62, 74 and 64 patients respectively had good, partial and poor control of asthma. More DPI users (36, 42.4%) had poor asthma control as compared to MDI users (28, 24.3%). MDI users reported better treatment adherence than DPI users (median [IQR] MAQ score 2 [1-3] vs 1 [1-3], p 0.043). As compared to DPI users, MDI users had significantly better median [IQR] TSQM domain scores for Effectiveness (72.2 [66.7-83.3] vs 66.7 [61.1-77.8], p 0.004), Convenience (72.2 [66.7-83.3] vs 66.7 [55.6-77.8], p 0.004), and Global Satisfaction (71.4 [64.3-78.6] vs 71.4 [57.1-78.6], p 0.035), but not Side Effects (100 [100-100] for both groups). These group differences remained significant after adjusting for MAQ scores in an ANCOVA model (p 0.020, 0.17, and 0.043 respectively for Effectiveness, Convenience and Global Satisfaction domains). TSQM Convenience and Global Satisfaction domain scores were significantly correlated with MAQ scores (Spearman’s coefficients 0.211 and 0.218 respectively, p 0.003 and 0.002 respectively). There was no significant correlation between any TSQM domain score and pulmonary function or measured FENO concentration.