On 2015 Feb 09, Edoardo Aromataris commented:

Thank you for your comment Wichor and for pointing this out for readers. You've highlighted how a simple detail in a search strategy and familiarization with the search platforms used can increase the specificity of the search markedly.

On 2015 Jan 29, Wichor Bramer commented:

I found a rather lage error in the search strategy as presented in this article, resulting in the retrieval of 26 times more irrelevant than relevant terms. When creating a complex search strategy it is very important to have the parentheses correct. The authors developed a search strategy in which they plan to search for P AND (I OR C) AND O, which is a god way (albeit maybe a bit too much elements). However the search string as shown on page 53 is constructed as (P) AND (I) OR (C) AND (O). PubMed alike other databases does not have a preset preference for Boolean operators, but just adds new elements in the order given. Constructed like this PubMed will retrieve all articles on Music Therapy and the desired outcomes, but not related to dementia. When using this search strategy in PubMed it currently retrieves 8000 references. When the parentheses are corrected only 300 articles remain, containing much more relevant references. Do watch closely when creating more complex searches that parentheses are placed correctly. Always fill them in yourself, and don't let PubMed decide that!

On 2015 Jan 29, Wichor Bramer commented:

I found a rather lage error in the search strategy as presented in this article, resulting in the retrieval of 26 times more irrelevant than relevant terms. When creating a complex search strategy it is very important to have the parentheses correct. The authors developed a search strategy in which they plan to search for P AND (I OR C) AND O, which is a god way (albeit maybe a bit too much elements). However the search string as shown on page 53 is constructed as (P) AND (I) OR (C) AND (O). PubMed alike other databases does not have a preset preference for Boolean operators, but just adds new elements in the order given. Constructed like this PubMed will retrieve all articles on Music Therapy and the desired outcomes, but not related to dementia. When using this search strategy in PubMed it currently retrieves 8000 references. When the parentheses are corrected only 300 articles remain, containing much more relevant references. Do watch closely when creating more complex searches that parentheses are placed correctly. Always fill them in yourself, and don't let PubMed decide that!

On 2015 Feb 09, Edoardo Aromataris commented:

Thank you for your comment Wichor and for pointing this out for readers. You've highlighted how a simple detail in a search strategy and familiarization with the search platforms used can increase the specificity of the search markedly.