Agreement of clinical tests for the diagnosis of peripheral arterial disease.

Abstract

The aim of this study was to compare different screening modalities in the detection of PAD in a primary care setting. Fifty participants living with Type 2 diabetes were recruited. Pulse palpation, waveform analysis, ankle brachial pressure index, absolute toe pressure, toe brachial pressure index and transcutaneous oxygen pressure were compared in the detection of peripheral arterial disease. One hundred limbs were included for analysis. This study showed different results in peripheral arterial disease screening tests in the same group of participants. The highest percentage of participants who had PAD was for the Doppler Waveform (93.0%). This was followed by TBPI (72.0%), ABPI (57.0%), ATP (35.0%), TCPO (30.0%) and pulse palpation (23.0%). The difference between these percentages is significant (p<0.0005). The magnitude of the effect size is medium/moderate (Cramer's V=0.498). This study demonstrates that inconsistencies exist between the agreement of the 6 different modalities used to detect PAD. These findings should create an awareness amongst clinicians when interpreting results of these tests. The authors advocate for urgent, more robust studies utilizing a gold standard modality for the diagnosis of PAD in order to provide evidence regarding which screening modalities would yield the most valid results.