I want to do a Cox regression taking repeated measurements into account. I want to fit a model looking at survival in a group of patients having a certain chronic disease. Levels of anxiety are measured at two timepoints spaced 10 years apart, and I want to see whether change in the level of anxiety influences survival.
My data are in long format:
Code:
+-----------------------------------------------+
| id PartDat HADSAnxi death enddate |
|-----------------------------------------------|
101. | 51 24 May 96 0 1 15feb2008 |
103. | 52 13 Jun 97 0 0 15jan2019 |
105. | 53 29 Sep 95 0 0 15jan2019 |
106. | 53 04 Jun 07 0 0 15jan2019 |
107. | 54 08 Oct 96 0 0 15jan2019 |
|-----------------------------------------------|
109. | 55 17 Jan 96 0 0 15jan2019 |
110. | 55 17 Aug 07 0 0 15jan2019 |
111. | 56 28 Nov 95 0 0 15jan2019 |
113. | 57 18 Dec 95 0 0 15jan2019 |
115. | 58 24 May 96 0 1 15feb2007 |
|-----------------------------------------------|
119. | 60 23 Oct 95 0 0 15jan2019 |
120. | 60 08 Oct 07 0 0 15jan2019 |
122. | 61 24 Jun 08 0 . 15jun2018 |
123. | 62 14 Feb 96 0 0 15jan2019 |
125. | 63 08 Nov 96 0 0 15jan2019 |
|-----------------------------------------------|
126. | 63 31 May 07 0 0 15jan2019 |
127. | 64 17 Jun 96 0 1 15mar2016 |
129. | 65 06 Dec 95 0 0 15jan2019 |
131. | 66 27 Feb 96 1 1 15mar1999 |
133. | 67 18 Mar 97 0 0 15jan2019 |
|-----------------------------------------------|
134. | 67 08 Apr 08 0 0 15jan2019 |
135. | 68 22 Nov 96 0 0 15jan2019 |
136. | 68 04 Feb 08 0 0 15jan2019 |
138. | 69 21 Nov 07 0 0 15jan2019 |
140. | 70 11 Jun 07 1 0 15jan2019 |
|-----------------------------------------------|
145. | 73 20 May 96 0 0 15jan2019 |
146. | 73 27 Feb 08 1 0 15jan2019 |
147. | 74 16 Dec 96 0 0 15jan2019 |
150. | 75 28 Aug 07 1 0 15jan2019 |
151. | 76 04 Mar 96 0 1 15nov2015 |
|-----------------------------------------------|
153. | 77 13 Dec 95 0 0 15jan2019 |
154. | 77 08 Feb 07 0 0 15jan2019 |
157. | 79 10 Jun 96 0 0 15jan2019 |
158. | 79 27 Apr 07 0 0 15jan2019 |
159. | 80 13 Mar 96 0 0 15jan2019 |
|-----------------------------------------------|
160. | 80 08 Oct 07 0 0 15jan2019 |
161. | 81 26 Mar 96 1 0 15jan2019 |
162. | 81 22 Nov 07 1 0 15jan2019 |
163. | 82 12 Sep 95 0 0 15jan2019 |
164. | 82 29 Aug 07 1 0 15jan2019 |
|-----------------------------------------------|
165. | 83 20 Feb 97 0 0 15jan2019 |
168. | 84 08 May 08 0 0 15jan2019 |
169. | 85 16 Apr 96 1 0 15jan2019 |
174. | 87 29 May 07 0 0 15jan2019 |
176. | 88 10 Apr 08 0 0 15jan2019 |
|-----------------------------------------------|
177. | 89 04 Mar 96 0 1 15aug2013 |
179. | 90 20 Jan 97 0 1 15apr2003 |
181. | 91 14 Aug 96 1 1 15sep2015 |
184. | 92 04 May 07 0 1 15jan2014 |
185. | 93 27 Mar 96 0 0 15jan2019 |
|-----------------------------------------------|
186. | 93 08 Jan 07 0 0 15jan2019 |
189. | 95 02 Oct 96 0 0 15jan2019 |
190. | 95 15 Nov 06 0 0 15jan2019 |
197. | 99 04 Mar 96 1 0 15jan2019 |
198. | 99 26 Nov 07 0 0 15jan2019 |
+-----------------------------------------------+
I used the user-written jm suite downloaded from http://www.stata.com/jmxtst, and created the syntax as described by Yulia Marchenko here: http://www.stata.com/meeting/nordic-..._marchenko.pdf.
I use the syntax suggested for combined datasets (longitudinal and survival):
Code:
jmxtstset idvar timevar, xt(is xt)|st(is st) failure(failvar) stsetopts where is xt and is st should be binary variables identifying longitudinal and survival observations, respectively (according to the slides above).
Code:
. jmxtstset id enddate, xt(HADSAnxi)|st(death) failure(death==1) variable death==1 not found
1) Is it not possible to specify failure using a binary variable like you could do with -stset-?
2) How should I specify is xt and is st?
3) Are there any online manuals available for jm, even though it's a preliminary command suite?
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