Record from visit ordered by date

[SASPhile]

SubjectID	Test_Name	Date	Collection_Time	Result_Value	Result_Units
123456	Height	6/8/2010	NA	1.53	m
123456	Height	6/22/2010	NA	1.51	m
123456	Height	NA	NA	1.51	m
123456	Weight	6/8/2010	NA	63	kg
123456	Weight	6/22/2010	NA	62	kg
123456	Weight	NA	NA	61	kg
123456	Weight	NA	NA	61	kg
456789	Height	8/12/2010	NA	1.36	m
456789	Height	NA	NA	1.36	m
456789	Height	7/30/2010	NA	1.36	m
456789	Weight	8/12/2010	NA	36	kg
456789	Weight	NA	NA	36	kg
456789	Weight	7/30/2010	NA	36	kg

Now if height is missing in all visits, then BMI is blank
if height is missing in one of the visits, take height from previous visits(from the last visit ordered by visit date)
if weight is missing in one of the visits, leave BMI blank

[PaigeMiller]

BMI is not present in this data set. Please explain further what you want to do and provide lots of details so we can understand your problem.

[SASPhile]

need to derive BMI. using below formula

BMI = Weight/(Height * Height)

[lakshmi_74]

data want(drop=new_bmi_height);
set have;
by subjectid date; retain bmi new_bmi_height;
if first.subjectid then do; bmi=0; new_bmi_height=0; end;
if missing(result_value) then
do;
if upper(test_name) eq 'HEIGHT' then bmi=new_bmi_height;
else if upper(test_name) eq 'WEIGHT' then bmi=0;
end;
else
do;
if upper(test_name) eq 'HEIGHT' then
do; bmi=/*Calculate BMI Value */; new_bmi_height=bmi; end;
else if upper(test_name) eq 'WEIGHT' then bmi=result_value;
end;
output;
run;

[SASPhile]

result_value is not BMI. it is actually weight and height values

[lakshmi_74]

You can upgrade easily how do you wish.