Stratified results with 1 entry strata left in  
Call:
clogit(fatall ~ beltuse + strata(case), data = pcrash)


                             coef exp(coef) se(coef)    z       p
beltuseProper restraint use 1.332     3.789    0.258 5.17 2.4e-07

Likelihood ratio test=32.9  on 1 df, p=9.68e-09
n= 949, number of events= 572 

 Stratified results with 1 entry strata removed   
Call:
clogit(fatall ~ beltuse + strata(case), data = pcrash, subset = (pcrash$case %in% 
    discordantcases))


                             coef exp(coef) se(coef)    z       p
beltuseProper restraint use 1.332     3.789    0.258 5.17 2.4e-07

Likelihood ratio test=32.9  on 1 df, p=9.68e-09
n= 384, number of events= 192 

 Stratified exact results  

 General regression exact results