****  Stata do file for meta-analysis of antiplatelet therapy for prevention of stroke **********

/*

See http://www.gllamm.org/bayes.html

Reference:
Chung, Y., Rabe-Hesketh, S. and Choi, I.-H. (2013). Avoiding zero between-study 
variance estimates in random-effects meta-analysis. Statistics in Medicine 32, 
4071-4089.

*/

* Install software (if needed)
ssc install gllamm, replace  
* download init_prior and calc_prior from http://www.gllamm.org/bayes.html
ssc install metaan, replace

* Load data (from http://www.gllamm.org/bayes.html)
use antiplatelet

* Calculate odds ratios and standard errrors
generate at = nt-dt
generate ac = nc-dc

generate or = (dt/at)/ (dc/ac)
generate lnor = ln(or)
generate seor = sqrt(1/dt+1/at+1/dc+1/ac)

generate id=_n

* ML (Section 2.2)
metaan lnor seor, ml

eq het: seor
constr def 1 [s1]seor=1 
gllamm lnor, i(id) s(het) nats constr(1) adapt eform

* REML (Section 2.2)
metaan lnor seor, reml


* BM (Section 7)
eq het: seor
constr def 1 [s1]seor=1 

gllamm lnor, i(id) s(het) nats constr(1) adapt  ///
   eform prior(gamma, scale(10000) shape(2))