Table 1

Baseline characteristics of included GPs and patients

GP (n=20)
Mean±SD/n (%)
Patients (n=19)
Mean±SD/n (%)
Sex (female, n (%))14 (70.0)Sex (female, n (%))17 (89.5)
Age (years, mean±SD)45.8±9.9Age (years, mean±SD)42.6±13.9
Practice experience as GP (years, mean±SD)14.4±10.0Educational level† (high, n (%))13 (68.4)
Number of patients in practice (mean±SD)6807±3104Requested for vitamin B12 (yes, n (%))11 (57.9)
SES of patients in practice*0.59±1.04Requested for vitamin D (yes, n (%))16 (84.2)
Intervention
 Online education (yes, n (%))12 (60.0)
 Education vitamin testing (yes, n (%))12 (60.0)
 Communication training (yes, n (%))13 (65.0)
 Received feedback (yes, n (%))16 (80.0)
 Patient information (yes, n (%))11 (55.0)
  • *SES data were retrieved from the SCP and linked by four digital postal codes to our data. SCP calculates social economic status scores based on information regarding education, income and position in the labour market. An SES score of 0 defines the mean socioeconomic status in the Netherlands. A score of >0 defines an SES higher than the mean in the Netherlands. A score of <0 defines an SES lower than the mean in the Netherlands.

  • †A high educational level was defined as an academic bachelor degree or higher.

  • GP, general practitioner; SCP, Social and Cultural Planning Office; SES, socioeconomic status.