An innovative approach based on real-world big data mining for calculating the sample size of the reference interval established using transformed parametric and non-parametric methods

Table 1 Sample size of establishment of RIs for thyroid-related hormones

Analytes	Biological variation (%)		Units	Method	Sample Size	Validation
Analytes	Biological variation (%)		Units	Method	Sample Size	LLW _CI /W _RI	ULW _CI /W _RI
TSH	Between-subject	35.0	µIU/mL	Transformed parametic method	239	0.037	0.194
TSH	Within-subject	21.2	µIU/mL	Non-parametric method	850	0.026	0.153
FT3	Between-subject	6.0	pg/mL	Transformed parametic method	75	0.170	0.168
FT3	Within-subject	16.5	pg/mL	Non-parametric method	179	0.149	0.178
FT4	Between-subject	7.7	ng/dL	Transformed parametic method	90	0.118	0.197
FT4	Within-subject	10.7	ng/dL	Non-parametric method	197	0.126	0.189
TT3	Between-subject	9.4	ng/mL	Transformed parametic method	97	0.096	0.227
TT3	Within-subject	12.2	ng/mL	Non-parametric method	192	0.138	0.198
TT4	Between-subject	6.4	µg/dL	Transformed parametic method	80	0.212	0.144
TT4	Within-subject	12.0	µg/dL	Non-parametric method	161	0.120	0.169

Data of biological variation derived from https://biologicalvariation.eu/ (2021.12.24)
LL, lower limits; UL,upper limits; W_CI, width of confidence interval; WRI, width of reference interval
Note: The bootstrap method was used to calculate 90% confidence intervals for the non-parametric method.

ISSN: 1471-2288