Hi Nick:
Thanks for the little tutorial. I had seen this true/false tool in answers before but didn't get it (& frankly, didn't bother to try). I can now envision making use of it -- thanks.
Eric
>Eric Wruck, Rafal Raciborski and Joseph Coveney made
>overlapping suggestions that all solved the problem,
>so there's almost nothing left to be said, but I'll
>say it anyway.
>
>For the general problem, the main ideas that make
>things easier are
>
>* looping over variables with -foreach-
>
>* using -substr()- or -index()- to look for substrings.
>
>My main comment is to emphasise a point tacit in most
>answers: you can exploit Stata's treatment of true and
>false directly in such problems, and not just indirectly.
>
>For example,
>
>gen OK = 0
>
>qui foreach v of var icd* {
> replace OK = OK + index(`v', "E11")
>}
>
>keep if OK
>
>works because any non-zero sum in -OK-
>is treated as true. Similarly, with
>the innermost statement instead
>
> replace OK = OK + (substr(`v',1,3) == "E11")
>
>the parenthesised expression evaluates
>to 0 or 1, and so the same trick will
>work: the criterion is whether the sum is
>non-zero (here, positive) or not.
>
>The "or" operator | naturally leads to
>the same conclusion.
>
>It is largely a matter of taste whether
>you do it this way or using lots of -if-
>conditions. The -if- route perhaps is
>closer to the way people actually
>think about the question, but doing
>it this way has a habit of growing on you.
>
>There is background at
>
>What is true and false in Stata?
>http://www.stata.com/support/faqs/data/trueorfalse.html
>
>King, Belinda L
>
>> > I am wanting to create a variable that tells me whether the
>> patient has an
>> > ICD10 starting with E11. I am not interested in the numbers
>> after the dots,
>> > nor am I interested in any of the other ICD10 codes and I
>> am wanting to drop
>> > patients who do not have E11 in one of the ICD10 columns. I
>> have tried
>> > playing with foreach, but this side of things is new for me
>> and I just keep
>> > getting messages telling me the syntax is incorrect. I would greatly
>> > appreciate any hints someone could give me, thank you in advance.
>> >
>> > +----------------------------------+
>> > | id icd10_1 icd10_2 icd10_3 |
>> > |----------------------------------|
>> > 1. | 1 K61.3 Z86.43 F05.9 |
>> > 2. | 2 B95.8 Z06.2 Z86.43 |
>> > 3. | 3 E11.69 R40.2 E11.9 |
>> > 4. | 4 Z86.43 Z95.8 E87.6 |
>> > 5. | 5 K59.0 K59.0 Z93.1 |
>> > |----------------------------------|
>> > 6. | 6 E11.65 E11.66 R63.4 |
>> > 7. | 7 E11.22 E66.9 E11.23 |
>> > 8. | 8 E11.9 E78.0 K63.50 |
>> > 9. | 9 E78.0 E11.65 D50.9 |
>> > 10. | 10 E11.65 K59.0 Z93.0 |
>> > +----------------------------------+
>> >
>
>*
>* For searches and help try:
>* http://www.stata.com/support/faqs/res/findit.html
>* http://www.stata.com/support/statalist/faq
>* http://www.ats.ucla.edu/stat/stata/
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
