The reliability of inspiratory resistive load magnitude and detection testing.

Objectives: To assess the test-retest reliability of inspiratory load detection and load magnitude perception tests in healthy volunteers.

Design: Cohort of convenience.

Setting: Respiratory physiology laboratory.

Participants: Twenty healthy adults.

Interventions: On two separate occasions participants performed tests of inspiratory loading. Participants breathed through custom made resistive tubing and were asked to indicate when they detected a different resistance during inspiration. In a second test participants rated the magnitude of presented inspiratory loads using the modified Borg score.

Main Outcome Measures: Intra-class Correlation Coefficient (ICC) values for repeated tests of inspiratory load detection threshold and load magnitude rating.

Results: ICC values ranged from 0.657-0.786 for load detection testing and 0.739 to 0.969 for rating of load magnitude.

Conclusions: The tests are simple and reliable measures of inspiratory load detection and magnitude rating. They can be used in future research to determine the effectiveness of interventions to reduce the effort of breathing in health and disease.