Table III.
Effect With and Without Modifiers on (A) SBP and (B) DBP Readings by Site Personnel and Trained Observer With Bias
| Effect Modification | Difference Between Site Personnel and Trained Observer | Effect Modification (Bias) | ||
|---|---|---|---|---|
| Effect modifier | With effect (not per‐protocol) | Without effect (per protocol) | Unadjusted | Adjusted |
| (A) | ||||
| Non–bare arm (sleeve) | 6.56 (3.21–9.91) | 1.68 (−1.10 to 4.45) | 4.88 (0.53–9.23) P=.028 | 4.25 (−0.85 to 9.35) P=.103 |
| Feet not flat | 3.42 (0.13–6.70) | 6.95 (3.44–10.46) | −3.54 (−8.34 to 1.27) P=.149 | −2.82 (−8.13 to 2.50) P=.299 |
| Conversation | 5.99 (2.62–9.36) | 2.22 (−0.80 to 5.24) | 3.77 (−0.75 to 8.29) P=.102 | 3.31 (−1.94 to 8.57) P=.216 |
| Arm/cuff not at heart level | 6.21 (1.52–10.90) | 3.58 (1.05–6.12) | 2.62 (−2.71 to 7.96) P=.335 | 1.32 (−5.83 to 8.47) P=.717 |
| Legs crossed | 3.39 (−1.86 to 8.65) | 4.10 (1.63–6.57) | −0.71 (−6.51, 5.10) P=.811 | −0.47 (−7.74 to 6.80) P=.899 |
| (B) | ||||
| Non–bare arm (sleeve) | −2.25 (−4.57 to 0.07) | −2.25 (−4.17 to −0.33) | −0.004 (−3.02 to 3.01) P=.998 | 1.41 (−2.73 to 5.55) P=.504 |
| Feet not flat | −1.63 (−4.04 to 0.79) | −3.67 (−6.24 to −1.09) | 2.04 (−1.49, 5.57) P=.261 | 2.56 (−1.66 to 6.79) P=.231 |
| Conversation | −1.86 (−4.21 to 0.48) | −2.31 (−4.41 to −0.21) | 0.45 (−2.71 to 3.60) P=.781 | −0.12 (−4.30 to 4.05) P=.954 |
| Arm/cuff not at heart level | −2.01 (−5.18 to 1.17) | −2.25 (−3.96 to −0.54) | 0.24 (−3.37 to 3.84) P=.897 | −1.87 (−7.50 to3.76) P=.526 |
| Legs crossed | −0.14 (−3.65 to 3.37) | −2.83 (−4.47 to −1.18) | 2.69 (−1.19 to 6.56) P=.174 | 2.77 (−2.97 to 8.51) P=.345 |
Abbreviations: DBP, diastolic blood pressure; SBP, systolic blood pressure. Factors that were not included in the effect modification analyses: inadequate rest time (all but 2 patients had <1 minute rest time), arm circumference measurement (0 for site personnel), and nonambient temperatures (11).