Validity of an electronic pressure algometer

BackgroundPressure algometry is one of a number of outcome measures that manual therapy practitioners are able to use in both clinical and research settings. The pressure algometer is used to determine the pressure pain threshold of specific muscle and bone locations.ObjectiveTo determine the validity of a commonly utilised electronic pressure algometer.DesignA repeated measures design was used.SettingBiomechanics Laboratory, Victoria University, Melbourne.MethodsA total of 300 measurements were collected from the electronic pressure algometer as it was applied perpendicularly to an AMTI force plate. Thirty (30) measurements were taken at five discrete rates of application; 10 kPa/s, 20 kPa/s, 30 kPa/s, 40 kPa/s and 50 kPa/s on two separate occasions. Maximum data were recorded from both the pressure algometer and force plate and analysed using the Intraclass Correlation Coefficient (ICC) statistic and the test for significant equality.ResultsICC values between the raw pressure algometer maximum values and the converted force plate data were high (ICC 0.905–0.998) for the two separate testing sessions and for both sessions combined (ICC 0.968–0.994). The test of significant equality revealed however that the data could not be considered as significantly the same even when allowing for a 5% or 10% tolerance.ConclusionThe results indicate that the electronic pressure algometer utilised in this study demonstrates limited validity in the laboratory setting.