Another blogging mom posted the following link http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0008169 to a study comparing institutionally raised orphans with community-raised orphans. The main outcome of this study is, according to the writers, a finding that children in institutional care actually had (slightly) higher ratings of emotional, physical and mental health than their community-raised peers.
I have a major problem with this study, and it is this - that 55% of the children in the community-raised "orphans" sample were actually in the care of one biological parent.
This completely throws off the results of the study, in my opinion. To compare children in an institutional (no biological caregiver) setting with children in, essentially, a single parent home is to compare apples and oranges. It is, to put a fine point on it, completely ignoring your main sample criteria.
Reading the methodology section leads me to believe that the reason for this is that they couldn't find a comparable sample size of true orphans in the community, so they expanded that group to include single-parent homes (under the very loose justification that the child was "abandoned" by one of their parents) in order to reach their required sample size. But that's not good science. You don't just change your parameters in order to make your quota. You especially do not change the parameters of one sample group while not making a comparable change to the other.
The study authors attempt to compensate for this massive flaw (which they somehow fail to mention in their study limitations) by conducting comparisons of the institutional care group with the true community-living orphans subgroup. The numbers, at first wag, appear to uphold the general correlations but there's a huge problem here as well. You are comparing groups of radically uneven size. Your institutional sample is more than double the size of the community living sample. That completely skews any statistical results.
Never mind the fact that all of the sample groups are extremely small in size. 1,500 kids is a very small sample when you consider that the current world orphan population is about 150 million. That's 0.001% in your sample. Making larger extrapolations to the full population based on 0.001% is nigh impossible. Hell, even if you total every child involved in this study (including the ones who shouldn't have been) you still have a ridiculously small population... from which the authors draw sweeping conclusions.
This study points to the fact that their samples are pulled from varying geographic areas as a strength. They state that the study cross-cuts cultural differences to provide more broadly applicable data. If you are going to do this, though, then there is no excuse for using pathetically small samples. Considering the fact that the majority of the world's orphans are from less economically developed nations, you should be able to find a very large sample across shared economic conditions. Expanding such a study to include nations that have a foster system, or a higher incidence of non-parental familial caregivers, should be fairly straightforward. That this was not done is mind-boggling.
In my opinion, this is just shoddy science. But it's a great idea to compare the effects of institutional care (in various cultures) to the effects of community-based care across specific age groups. It's an even better idea to compare the end results - adult "graduates" of both care models. This study takes a great idea and hoses it.