19.5.1  General approach

Most PMAs will use similar general analysis techniques to that of retrospective IPD meta-analyses. These techniques are outlined in detail in Chapter 18 (Section 18.4) and include the general approach to these analyses and the ability to undertake time-to-event analyses (if appropriate). The use of patient-level data also permits more statistically powerful subgroup analyses and multilevel modelling to explore associations between intervention effects and patient characteristics, as well as prognostic modelling in some cases. Chapter 18 (Section 18.4.7) describes some of the potential software packages that can be used to analyse these types of data.