|
PREDICTABILITY OF BRACHIORADIALIS
REFLEXOMETRY Two
targets of normality were developed; RMR change >350 kcals. and
Fire - Prefire intervals < 66 msecs. People that achieved the RMR
(gold standard) target
had a mean RMR measured at 2040.7 kcals. Therefore the RMR norm for
euthyroid individuals was considered to be >
2000 kcals. There
were 179 people in the subpopulation of patients on no medication. There
were 117 people identified as positive (hypothyroid) by RMR criteria and
123 people identified as positive by Reflex criteria. There were 58 people
identified as negative (euthyroid) by RMR criteria and 57 people
identified as negative by Reflex criteria. These numbers allow the
construction of the following table:
Sensitivity
is the proportion of those that are hypothyroid that are correctly
diagnosed. It is expressed as:
________True Positives_______ = __117__
= 0.992
True Positives + False Negatives
117 + 1 Specificity
is the proportion of those that are euthyroid that were correctly
identified. It is expressed as:
________True Negatives_______
= ___58___
= 0.906
True Negatives + False Positives
58 + 6
Predictive
Value of a Positive Test
is the proportion of those with a positive test that are hypothyroid. It
is expressed as:
________True Positives_______
= ___117__
= 0.951
True positives + False Positives
117+6
Predictive
Value of a Negative Test
can be considered as the proportion of those with a negative test that are
hypothyroid; which is expressed as:
_______False Negatives_______
= _____1____
=
0.017
False Negatives + True Negatives
1 + 58
More commonly Predictive Value of a Negative Test is considered the proportion of those with a negative test who are euthyroid: which is expressed as: _______True Negatives_______ = ___58___ = 0.983 False Negatives + True Negatives 1 + 58
|