2.2. Subjects
The total sample comprised 364 patients (54% female) with a
mean age of 42.6 years (SD¼13.2). The sample was divided by
recruitment period. The first cohort (n¼169) recruited from March
2009 until December 2010 comprised 51.2% female patients with a
mean age of 42.3 (SD¼12.9) years. The second cohort (n¼197)
recruited from January 2011 until April 2012 had a mean age of
42.8 (SD¼13.6) years and with 56.1% female. As the latter cohort
was larger, it was used as the development sample and the earlier
cohort as the validation sample.