Skip to main content

Table 3 Variation in DINAMAP™ measurements of the ankle-brachial index by subgroup defined at the first measurement

From: The reliability of the ankle-brachial index in the Atherosclerosis Risk in Communities (ARIC) study and the NHLBI Family Heart Study (FHS)

   Square root of variance components   
Subgroup N Between-person Within-person Total Reliability Coefficient Within-person CV, %
Overall 119 0.133 0.106 0.170 0.612 9.0
Age, y       
   ≤ 62 66 0.124 0.104 0.162 0.587 8.9
   > 62 53 0.144 0.107 0.180 0.643 9.1
Race/ethnicity       
   African American 19 0.098 0.079 0.125 0.606 6.8
   White 100 0.139 0.110 0.177 0.614 9.3
Gender       
   Male 49 0.140 0.102 0.173 0.653 8.4
   Female 70 0.122 0.109 0.163 0.555 9.5
Field center       
   Forsyth County, NC 77 0.127 0.116* 0.172 0.545 9.9*
   Minneapolis, Minn 42 0.142 0.086* 0.166 0.732 7.2*
Body mass index, kg/m2       
   ≤ 27 61 0.141 0.083* 0.164 0.741* 7.1*
   > 27 58 0.124 0.126* 0.178 0.495* 10.7*
Diabetes       
   No 106 0.134 0.099 0.167 0.646 8.4
   Yes 13 0.112 0.150 0.187 0.358 13.3
Hypertension       
   No 76 0.128 0.100 0.163 0.622 8.3
   Yes 43 0.134 0.116 0.177 0.574 10.1
Hypertension rx switch       
   No 101 0.136 0.104 0.171 0.630 8.8
   Yes 18 0.114 0.115 0.162 0.498 9.9
Coronary heart disease       
   No 88 0.129 0.098 0.162 0.638 8.3
   Yes 31 0.148 0.116 0.188 0.619 9.9
Legs       
   Same 51 0.115 0.118 0.165 0.486* 10.0
   Different 68 0.146 0.094 0.174 0.706* 8.6
Days between measures       
   ≤ 240 60 0.131 0.107 0.169 0.602 9.1
   > 240 59 0.136 0.103 0.171 0.633 8.7
FHS sampling group       
   African American 19 0.098 0.079 0.125 0.606 6.8
   High family risk score 68 0.148 0.114 0.187* 0.629 9.7
   Random sample 32 0.117 0.099 0.153* 0.581 8.2
  1. *p < 0.05 for the difference between the two subgroups (the 95% bootstrapped confidence interval for the difference did not include zero).
  2. Proportion too small to perform statistical tests of differences.
  3. "No" includes those who were either taking or not taking hypertension medication at the time of both ABI measures; "yes" includes those who were taking hypertension medication at the time of one ABI measure and not taking hypertension medication at the time of the other ABI measure.