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. 2019 Dec 4;20:450. doi: 10.1186/s12882-019-1634-1

Table 2.

Changes in step count per HD and non-HD day, intraclass correlation coefficients and number of days of activity monitoring required to obtain representative PA data across a range of minimum wear time criteria

HD step count ICCs Number of days neededa Number of days neededb Non-HD step count ICCs Number of days neededa Number of days neededb
Wear time criteria (hours) N Day 1 Day 2 Day 3 N Day 1 Day 2 Day 3
≥ 1 62 3249 ± 3481 3896 ± 3266 3050 ± 3195 0.723 1.53 2 65 5126 ± 5173 3499 ± 3992 4906 ± 4688 0.559 3.16 4
≥ 2 60 3318 ± 3518 3993 ± 3272 3139 ± 3210 0.719 1.56 2 64 5023 ± 4977 3462 ± 4026 4713 ± 4458 0.586 2.83 3
≥ 3 57 3308 ± 3610 3986 ± 3355 3207 ± 3270 0.723 1.53 2 63 5024 ± 5017 3517 ± 4034 4714 ± 4494 0.588 2.80 3
≥ 4 55 3288 ± 3670 3912 ± 3350 3241 ± 3299 0.744 1.38 2 63 5024 ± 5017 3517 ± 4034 4714 ± 4494 0.588 2.80 3
≥ 5 52 3514 ± 3694 4096 ± 3367 3541 ± 3274 0.729 1.49 2 63 5024 ± 5017 3517 ± 4034 4714 ± 4494 0.588 2.80 3
≥ 6 44 3676 ± 3897 4091 ± 3519 3744 ± 3412 0.764 1.24 2 62 5066 ± 5046 3511 ± 4067 4688 ± 4526 0.591 2.77 3
≥ 7 38 3340 ± 3561 4030 ± 3720 3748 ± 3484 0.815 0.91 1 62 5066 ± 5046 3511 ± 4067 4688 ± 4526 0.591 2.77 3
≥ 8 32 3382 ± 3811 4300 ± 3939 3817 ± 3733 0.827 0.84 1 61 5317 ± 5232 3522 ± 3974 4775 ± 4524 0.614 2.51 3
≥ 9 28 3750 ± 3942 4455 ± 4127 4099 ± 3891 0.831 0.81 1 61 5317 ± 5232 3522 ± 3974 4797 ± 4518 0.615 2.50 3
≥ 10 25 3998 ± 4098 4584 ± 4275 4107 ± 4011 0.847 0.72 1 61 5317 ± 5232 3522 ± 3974 4797 ± 4518 0.615 2.50 3
≥ 11 15 3855 ± 3983 4707 ± 4348 4338 ± 4584 0.875 0.57 1 59 5456 ± 5314 3524 ± 3950 4885 ± 4555 0.602 2.64 3
≥ 12 11 3270 ± 3427 4479 ± 4434 3962 ± 4576 0.839 0.77 1 53 5712 ± 5457 3601 ± 4086 5211 ± 4680 0.611 2.55 3

ICC Intraclass correlation coefficients, HD Haemodialysis. aA minimum number of days needed to achieve an ICC of 0.80 calculated using the Spearman-Brown prophecy formula; bEstimates from the Spearman-Brown prophecy formula should be rounded up (e.g. an estimate of at least 1.2 days should be interpreted as at least 2 days because 1 will be insufficient to achieve an ICC ≥ 0.8