. 2010 Oct 29;55(2):180–191. doi: 10.1093/annhyg/meq075

Table 2.

Correlation coefficient, average difference, and correction factors between pair of the samplers

Sampler pairs	Sample number	Correlation coefficient (P value)	Average difference between the groups (mg m⁻³) (P value)^a	Correction factors^b
ACCU-CAP™/ACCU-CAP™	29	0.26 (0.264)^c	6.66 (0.324)^c	0.16 ± 0.50^c
ACCU-CAP™/Button	30	0.94 (<0.001)	0.10 (0.885)	0.91 ± 0.46
ACCU-CAP™/CIP10-I	30	0.87 (<0.001)	1.08 (0.267)	0.60 ± 1.52
ACCU-CAP™/GSP	33	0.95 (<0.001)	0.98 (0.709)	0.77 ± 0.75
ACCU-CAP™/IOM	32	0.46 (0.008)	0.55 (0.270)	0.64 ± 0.38
Button/Button	30	0.96 (<0.001)	0.03 (0.933)	0.97 ± 0.34
Button/CIP10-I	32	0.22 (0.219)	0.33 (0.529)	0.82 ± 1.18
Button/GSP	30	0.32 (0.087)	0.29 (0.404)	0.79 ± 0.57
Button/IOM	24	0.80 (<0.001)	0.05 (0.913)	0.95 ± 0.52
CIP10-I/CIP10-I	24	0.94 (<0.001)	0.27 (0.714)	1.13 ± 1.02
CIP10-I/GSP	30	0.70 (<0.001)	0.11 (0.871)	1.08 ± 0.35
CIP10-I/IOM	28	0.99 (<0.001)	0.22 (0.924)	1.08 ± 0.39
GSP/GSP	30	0.91 (<0.001)	0.17 (0.734)	0.88 ± 0.26
GSP/IOM	31	0.91 (<0.001)	0.03 (0.982)	0.99 ± 0.39
IOM/IOM	31	0.74 (<0.001)	0.75 (0.573)	0.74 ± 0.74

Average difference between the groups was calculated using absolute value difference between the sampler groups.

Correction factors is applied to the second sampler to make average mass concentration same as the first sampler in sampler pairs; ± indicates 95% confidence interval value.

Correlation coefficient becomes 0.83 (P < 0.001), the average difference becomes 0.01 mg m⁻³ (P = 0.98), and the correction factor becomes 1.02 ± 0.50 with the removal of a single outlier.