Hello R users!

I am a medic and have been working with R for about 6 months now.

I was hoping to pick someone’s brain about a diagnostic accuracy study that has now been completed.

I am trying to derive the sensitivity, specificity, NPV and PPV with the corresponding 95% CI from the raw data.

My data is in a data frame as below


g.s	t1	t2	t3	t3	t4	t5	index
Yes	1	1	1	1	1	1	1
Yes	1	1	1	1	1	1	2
Yes	1	1	1	1	1	1	3
Yes	1	1	1	1	1	1	4
Yes	1	1	1	1	1	1	5


Each row represents a patient with a unique id (variable: index).

g.s is a binary variable ans represents the results from the gold standard (yes / no).

t1 to t5 are the tests at different thresholds being tested.

t1 to t5 are all binary variables with 1 as yes and 0 as no.

Now i could create separate 2 x 2 tables for each threshold (t1 to t5) against the gold standard and subsequently derive sense, spec, NPV and PPV plus their 95 % CI for each threshold (t1 to t5).

I was however wondering if there was a more efficient way to get these results from the raw data in R.

Hope I have explained my self clearly and thanks a lot in advance!!

Cheers

Anoop
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