在超过特定阈值的列中查找行内的数字组

Question

I'm trying to identify "responders" in a data set as defined by a patient having a certain clinical metric be >= 2 across 4 weeks.

I have a data set for patients of the below format, but for many more:

pt_num   week_0   week_1    week_2   week_3   week_4   week_5   week_6  week_7   week_8
   1        0       2          3       3        4         3       2       1         1
   2        0       2          3       3        1         3       2       1         1

In the example above patient 1 would be a responder, patient 2 would not.

I have an idea on how to do this through looping over every row and cell - but I'm hoping there is a much more efficient way to do this - any help appreciated.

Answer 1

We can use rle row-wise and check if there is at least one instance of 4 consecutive weeks where a metric is greater than equal to 2.

apply(df[-1], 1, function(x) any(rle(x >= 2)$lengths >= 4))
#[1]  TRUE FALSE