Language: ASPPB offers a French form of the EPPP (the FEPPP) where a licensing authority legally requires one. ASPPB has not yet published the competency statements in French, so our questions and cards are in English until it does.

3.B.1

Choosing by evidence: efficacy, effectiveness and comparisons

ASPPB's competency statement 3.B.1: Plan and implement treatments/interventions based on assessment findings and research, including evidence for their comparative efficacy and effectiveness

A plan starts from the assessment and from what research shows works for the problem found. Efficacy trials show whether a treatment can work under controlled conditions; effectiveness studies show whether it works in routine care with typical clients. Comparative evidence shows whether one active treatment outperforms another, which often it does not by much. The quality of the evidence matters too: a large effect from weak studies supports a plan less than it seems.

Key ideas

Efficacy: How well a treatment works in controlled trials, usually randomized, with defined samples and trained therapists. Chambless and Hollon (1998) give efficacy trials the greatest weight and require independent replication before a treatment is called established.
Effectiveness: How well a treatment works in routine settings and with varied populations. Chambless and Hollon (1998) say efficacy trials should be followed by effectiveness research in clinical settings and by cost-effectiveness research.
Comparative efficacy: Whether one active treatment beats another. In comparative trials of seven major psychotherapies for mild to moderate depression, there were no large differences in efficacy (Cuijpers and colleagues, 2008), so other factors often decide.
Quality of evidence: Large effects against a wait list can rest on weak trials. For binge-eating disorder, Hilbert and colleagues (2019) found large effects of psychotherapy against inactive controls yet rated the quality of evidence for binge-eating outcomes generally very low.

Worked example

A 38-year-old teacher meets criteria for binge-eating disorder, with weekly binges and no purging. Individual therapy at the clinic has a three-month wait, a structured self-help program based on CBT with brief check-ins can start now, and her physician has mentioned medication.

Start from the assessment: binge-eating disorder with no compensatory behavior and no medical urgency, so outpatient options fit.
Efficacy: in a meta-analysis of 81 trials, psychotherapy, mostly CBT, had large effects on binge eating against inactive controls, structured CBT-based self-help medium to large effects against wait lists, and medication mostly small effects against placebo (Hilbert and colleagues, 2019).
Comparisons: against active treatments there was limited evidence that any one was superior, and combined treatment added nothing for binge eating over time, so access and her preferences can tip the choice.
Plan: offer guided self-help now with weekly tracking of binges, and step up to individual CBT if the frequency does not fall, rather than waiting three months untreated.

Read the head-to-head comparisons and the quality of the evidence, not only whether a treatment beat a wait list.

Check yourself

Two psychotherapies for mild to moderate depression have each outperformed wait-list conditions. What does comparative research suggest about choosing between them?

Practise 3.B.1

Sources

Chambless and Hollon (1998), Defining empirically supported therapies, Journal of Consulting and Clinical Psychology (PMID 9489259), Abstract; efficacy, replication and effectiveness research
Cuijpers, van Straten, Andersson and van Oppen (2008), Psychotherapy for depression in adults: a meta-analysis of comparative outcome studies, Journal of Consulting and Clinical Psychology (PMID 19045960), Abstract; results and conclusions
Hilbert, Petroff, Herpertz, Pietrowsky, Tuschen-Caffier, Vocks and Schmidt (2019), Meta-analysis of the efficacy of psychological and medical treatments for binge-eating disorder, Journal of Consulting and Clinical Psychology (PMID 30570304), Abstract; results and quality of evidence
Bower and Gilbody (2005), Stepped care in psychological therapies: access, effectiveness and efficiency, British Journal of Psychiatry (PMID 15630118), Abstract; the stepped care model