order of approximation used in glmmPQL

Dear all, 

Could anyone let me know what order of approximation (first, second or 
higher order) is used in glmmPQL in the MASS library please? I have 
read the section on this wrapper command in Venables and Ripley but am 
not sure if the relevant information is there. 

Many thanks in advance. 

Best wishes,
Edmond


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Edmond Ng 
Research Fellow
Graduate School of Education
35 Berkeley Square
Bristol
BS8 1JA
United Kingdom