My research topic is “The impact of Prolonged Isolation in Relation to Space Travel”.  Since there is not a good way to conduct an actual experiment studying this without sending humans on a long duration space flight I decided that the best way to study this is to gather information that studies confinement effects on mental health as well as studies that show the effects of cramped conditions on mental health.
My first search was in PubMed.gov for psychiatric disorders and isolation.  It returned 23809 results.
The second search I did was in the same database for psychiatric disorders and confinement.  It returned  2621 results.
The third search was also in PubMed.gov and was for mental health and confinement.  This search returned 1069 results.
The fourth search I did in the the Sage Premier database.  I searched for mental health and confinement in this database and it returned 30379 results.
The fifth search that I did was in the Sage Premier database.  I searched for psychiatric disorders and isolation this search returned 25027 results.
From what I can tell I have plenty of information and sources to start my research project.  I think that I have reached saturation.  Several of the searches I did this time returned papers that were relevant and I will likely be able to use them.