The reliability of the ankle brachial index: a systematic review

Abstract

Background The ankle brachial index (ABI) is widely used in clinical practice as a non-invasive method to detect the presence and severity of peripheral arterial disease (PAD). Current guidelines suggest that it should be used to monitor potential progression of PAD in affected individuals. As such, it is important that the test is reliable when used for repeated measurements, by the same or different health practitioners. This systematic review aims to examine the literature to evaluate the inter- and intra-rater reliability of the ABI. Methods A systematic search of MEDLINE, EMBASE and CINAHL Complete was conducted to 20 January 2019. Two authors independently reviewed and selected relevant studies and extracted the data. Methodological quality was determined using the Quality Appraisal of Reliability (QAREL) Checklist. Results Fifteen studies of ABI reliability in a range of patient populations were identified as suitable for inclusion in the review: seven considered inter-rater reliability, four intra-rater reliability, and four studies evaluated both inter- and intra-rater reliability. Inter-rater reliability was found to be highly variable, with intraclass correlation coefficients (ICC’s) ranging from poor to excellent (ICC 0.42–1.00), while intra-rater also demonstrated considerable variation, with ICCs from 0.42–0.98. Meta-analysis was not possible due to the lack of statistical information reported. Conclusions Results of included studies suggest the inter- and intra-tester reliability of the ABI is acceptable. However, inconsistencies in obtaining systolic pressure measurements, calculating ABI values, and incomplete reporting of methodologies and statistical analysis make it difficult to determine the validity of the results of included studies. Further research, with more consistent reliability methodology, statistical analysis and reporting conducted in populations at risk of PAD is needed to conclusively determine the ABI reliability.

Use of Noncontact Infrared Skin Thermometer for Peripheral Arterial Disease Screening in Patients With and Without Diabetes

“…29,30 In the present study, we found that an accurate handheld thermometer allows detecting baseline foot skin temperature with high reproducibility by avoiding factors influencing foot skin temperature levels. Regarding reliability, interrater reliability of ABI showed varied data from poor to excellent (ICC: 0.42-1.0) in the recent meta-analysis, 31 but that of our method was excellent (ICC: 0.94), which was very high. It is superior to ABI that our method has good reliability without special training.…”

Multimodal Supervised Exercise Training Is Effective in Improving Long Term Walking Performance in Patients with Symptomatic Lower Extremity Peripheral Artery Disease

“…The clinical relevance of these changes remains questionable. ABI and TBI have been described to have a heterogeneous reliability, affected by co-morbidities such as medial arterial calcification and diabetes [ 36 , 37 ]. Therefore, we consider that our results, even if statistically significant, have no clinical repercussions.…”

Peripheral Artery Disease as a Predictor of Coronary Artery Disease in Patients Undergoing Coronary Angiography

“…ABI has been shown to be a non-invasive, sensitive, specific, and cost-effective tool for lower limb vascular assessment and evaluating atherosclerosis in lower limbs. It represents the ratio of the ankle to brachial systolic pressure and is calculated by dividing the higher systolic pressure of the dorsalis pedis and tibialis posterior vessels at the ankle with that measured in the brachial artery in both arms [ 14 ]. An ABI below 0.9 is considered a powerful independent marker of coronary morbidity and mortality [ 15 ].…”