Background The established mental health care system does not have the resources to meet the extensive need for care of those with anxiety and depressive disorders. Paraprofessionals partially replacing professionals may be cost-effective. Objectives To investigate the effectiveness of any kind of psychological treatment for anxiety and depressive disorders performed by paraprofessionals compared with professionals, waiting list or placebo condition. To examine whether the results apply to clinically significant anxiety and depressive disorders of referred patients with a psychiatric history and/or whose illness has lasted two years or more. Search strategy CCDANCTR-Studies using the following terms: (paraprofessional* or para-professional* or non-professional* or non-professional* or peer or volunt*); EMBASE (ExerptaMedica), MEDLINE and PsycINFO, all years published, key words: para-/paraprofessional, non-/nonprofessional, rand*, respectively psy*; citation lists of articles reviewing the subject and included studies; correspondence with authors of controlled studies and review reports on the subject. Selection criteria Randomised controlled trials that used symptom measures, and compared the effects of psychological treatments given by paraprofessionals (mental health care workers, paid or voluntary, unqualified with respect to the psychological treatment) with psychological treatments given by professionals, and with waiting list or placebo condition. Data collection and analysis The standard mean difference was used to pool continuous data from each trial, and odds ratios were used to pool dichotomous data, using a random effects model. The generic inverse variance method was used for combining continuous and dichotomous data. The effect of low quality studies and the use of self-rated versus observer-rated measures were tested, and subgroup analyses were performed for differences between depression and anxiety diagnosis, paraprofessionals with/without professional background, group/individual intervention, length of follow-up and gender (post-hoc subgroup analysis). Main results Five studies, all using self-report measures, reported five comparisons of paraprofessionals versus professionals (n=106) and five comparisons of paraprofessionals versus control condition (n=220). No differences were found between paraprofessionals and professionals (SMD=0.09, 95% CI -0.23 to 0.40, p=0.58; no significant heterogeneity). Studies comparing paraprofessionals versus control reported mixed continuous and dichotomous data showed a significant pooled effect in favour of paraprofessionals (OR=0.34, 95% CI 0.13 to 0.88, p=0.03), but heterogeneity was indicated (I-2=60.9%, Chi(2)=10.24, df=4, p=0.04). After correction for heterogeneity and removing one study of low quality, the pooling of data from three studies (n=128; mixed gender and women only) indicated no significant difference in effect between paraprofessionals and professionals (SMD=0.13, 95% CI -0.39 to 0.64; p=0.63) and a strongly significant pooled effect for three studies (n=188; women only) favouring paraprofessionals over the control condition (OR=0.30, 95% CI 0.18 to 0.48, p<0.00001), and homogeneity indicated between studies (I-2=0%, Chi(2)=0.47, df=2, p=0.79). Authors' conclusions The few studies included in the review did not allow conclusions about the effect of paraprofessionals compared to professionals. Pooling data from three studies, involving women only, indicated a significant effect for paraprofessionals (all volunteers) compared to no treatment. The evidence to date may justify the development and evaluation of programs incorporating paraprofessionals in treatment programs for anxiety and depressive disorders.
