From the identified studies and respective populations we recorded publication reference, total number of participants, country, sex, age (mean, median, or range), recruitment time, follow-up (years), outcome reported (stroke, cardiovascular disease) and method of outcome assessment, number (rate) of events, method of assessing salt intake, and level of salt intake in different categories.
Another kind of short-range recruitment was described in O. longinoda major workers that emit mandibular gland secretions [19], [20].
This marking behavior seems to correspond to a new kind of short-range recruitment as the number of workers increased in the focal circle.
In Oecophylla, an ant genus comprising two territorially dominant arboreal species, workers are known to (1) use anal spots to mark their territories, (2) drag their gaster along the substrate to deposit short-range recruitment trails, and (3) drag the extruded rectal gland along the substrate to deposit the trails used in long-range recruitment.
In already-known cases of short-range recruitment involving territorial marking (including in Oecophylla), workers run in short, looping circles while dragging their gaster onto the substrate and attract nestmates situated in a radius of 10 to 30 cm [4], [23] [26].
By utilising strategic and broad ranging recruitment techniques however, the best available study population can be achieved under difficult research constraints.
For many other conditions, particularly those that dominate the older age ranges, recruitment was very low, as can be seen more clearly in Table III where first line trial entry proportions are distributed by age at diagnosis and diagnostic category.
29 A wide range of recruitment methods was employed, including the use of recruitment posters in general practices and rheumatology clinics, information packs handed out by members of the study advisory group, information put on local and national gout support group websites, and other online advertising sites.
Clinics are free to employ a range of recruitment strategies to identify and recruit potential participants, depending on what is deemed appropriate for each clinic.
Intervention delivery in these settings has previously been identified as a characteristic of successful interventions among people living with HIV [ 38], though a wider range of recruitment settings may be necessary to recruit sufficient numbers, and relevant risk groups, of MSM [ 39].
Recruitment is critical to the success of any course and the wide range of recruitment approaches reported in parenting interventions and parenting focussed obesity prevention interventions [ 34- 39] indicate the difficulties associated with parental recruitment.
