Confidence Interval of Reference Range Limit Calculator
Online calculator which helps to estimate the confidence interval of a standard reference range limit (LlciLlrr, UlciLlrr) from the standard deviation of a standard reference range limit (SDSRRL).
Estimate LlciLlrr, UlciLlrr from SDSRRL
Online calculator which helps to estimate the confidence interval of a standard reference range limit (LlciLlrr, UlciLlrr) from the standard deviation of a standard reference range limit (SDSRRL).
Code to add this calci to your website
Formula:
Lower Limit = m - t0.975,n-1 x √((n+1)/n) x s.d
Upper Limit = m + t0.975,n-1 x √((n+1)/n) x s.d
SDSRRL = s.d / 2
LlciLlrr = Llrr - t0.975,n-1 x √((n+1)/n) x SDSRRL
UlciLlrr = Llrr + t0.975,n-1 x √((n+1)/n) x SDSRRL
LlciUlrr = Ulrr - t0.975,n-1 x √((n+1)/n) x SDSRRL
UlciUlrr = Ulrr + t0.975,n-1 x √((n+1)/n) x SDSRRL
Where,
t - Distribution.
s.d - Standard Deviation
n - Total Count
m - Mean
LlciLlrr - is the Lower limit of the confidence interval of the Lower limit of the standard reference range
UlciLlrr - is the Upper limit of the confidence interval of the Lower limit of the standard reference range
LlciUlrr - is the Lower limit of the confidence interval of the Upper limit of the standard reference range
UlciUlrr - is the Upper limit of the confidence interval of the Upper limit of the standard reference range
SDSRRL - is the standard deviation of the standard reference range limit
Llrr - is the Lower limit of the standard reference range
Ulrr - is the Upper limit of the standard reference range
Note:
97.5% percentile with (n-1) degrees of freedom corresponds to t0.975,n-1 from the Student's t-distribution table.
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