This is a system of putting together your search terms.
Boolean operators are: AND, OR, and NOT.
They do not always have to be capitalized but some databases do require that they are. You use these operators to put together the terms that you want to use for your search--you use OR between terms that are functionally equivalent for your purposes (teenager OR adolescent), AND between terms that you want your results to contain both/all of (teenager AND diabetes), and NOT for any terms that you want entirely excluded (meaning that any document containing that term within its searched data will not be brought back).
Parentheses are used around terms that you are ORing together so that the system doesn't get confused when you have a search string that includes ANDs and ORs. For examples: (teenager OR adolescent) AND diabetes
This is a way of indicating that you are interested in additional variations on a string of letters. Most systems use * for truncation.
For example, teen* will get you all words that start with that initial string: teen, teens, teenager, teenagers, teenaged. Sometimes this can be very helpful, sometimes you may find you get too many variations. For example: arm* will get you arm and arms, but also army and armies.
The databases PubMed, CINAHL, Embase, and PsycINFO were searched in March 2020. The concepts searched for were smart phones, type 1 diabetes, and adolescents. In each database, search terms and subject headings were used. In PubMed, the following search string was used: (“smart phones”[tiab] OR smartphone*[tiab] OR iPhone*[tiab] OR "Smartphone"[Mesh]) AND (diabetes[tiab] OR "Diabetes Mellitus, Type 1"[Mesh]) AND (teen*[tiab] OR adolescen*[tiab] OR "Adolescent"[Mesh]).
The search was limited to studies published after 2006 since the first iPhone was introduced in 2007. Studies that were not primary research were excluded, as well as articles that were in a language other English or Spanish.