Dynamic Psychotherapy The dynamic psychotherapies represent the oldest treatments for depression. Early findings were generally unimpressive, although the approach was often included as a comparator by investigators with other allegiances. For example, McLean and Hakstian found brief dynamic therapy less efficacious than their preferred behavioral intervention or medications[
14] and Covi and colleagues found dynamic group psychotherapy no better than placebo and less efficacious than medications in one study[
15] and less efficacious than CBT (with or without medications) in another.[
16] No differences were found relative to social-skills training[
17] or self-control therapy[
18] in a pair of studies implemented by behaviorally-oriented researchers and few differences were found between psychodynamic interpersonal psychotherapy and CBT in a pair of studies by investigators with little expertise with CBT.[
19,
20]
Recent studies by investigators with expertise in dynamic psychotherapy have been somewhat more supportive but still less than wholly compelling. A study by Cooper and colleagues in England found that psychodynamic psychotherapy did not differ from CBT or non-directive counseling and that each produced greater change on measures of depression than did routine primary care in the treatment of postpartum depression.[
21] A study by Burnand and colleagues in Switzerland found that adding dynamic psychotherapy to medication reduced the proportion of patients who met criteria for MDD following treatment and led to better work adjustment, although there were no differences on measures of depressive symptoms.[
22] A study by Salminen and colleagues in Finland on patients with mild-to-moderate MDD in a general practice setting found no differences between short-term dynamic psychotherapy versus fluoxetine antidepressant medication, but the sample was too small to draw firm conclusions.[
23] De Jonghe and colleagues in the Netherlands found that adding short-term dynamic psychotherapy increased the proportion of patients responding to medications by virtue of reducing rates of attrition[
24] and that patients with personality disorders may have been more likely to respond to combined treatment than to medications alone.[
25] A subsequent study by this same group found that antidepressant medications worked more rapidly than short-term dynamic psychotherapy and were superior after eight weeks of treatment.[
26] Maina and colleagues in Italy found that brief dynamic therapy was no more efficacious than brief supportive psychotherapy when added to medications at the end of treatment, but that patients continued to improve over a subsequent six-month continuation phase[
27] and that patients previously treated with dynamic psychotherapy were less likely to experience a recurrence over a subsequent 48-month treatment-free follow-up.[
28]
One of these studies found clear evidence of efficacy relative to routine care[
21] and adding psychodynamic psychotherapy enhanced the efficacy of medication on at least some measures in a second,[
22] and for at least some patients in a third.[
24,
25] This is better than it had done in those earlier trials. Perhaps most interesting were the indications that patients treated with brief dynamic psychotherapy plus medications continued to improve after the end of active treatment[
27] and were less likely to recur than patients previously treated with supportive psychotherapy plus medications.[
28] At the same time, none of these studies found dynamic psychotherapy superior to a nonspecific control or alternative treatment; results were more promising than early trials but hardly impressive.
Dynamic psychotherapy has rarely been tested in the treatment of geriatric depression, but the samples studied have been so small and the quality of the alternative interventions suspect; it is not clear that anything but null findings would have been expected. Gallagher and Thompson found few differences between brief dynamic therapy and either CBT or BT,[
29] findings replicated in a second study in which all three active treatments pooled were superior to a wait list control.[
30] Treatment gains produced by either CBT or BT were better maintained than those produced by dynamic therapy in the first study but not in the second.[
31] A third study by this group found that short-term caregivers did better in brief psychodynamic psychotherapy than they did in CBT, whereas long-term caregivers showed the opposite pattern.[
32] Conversely, Steuer and colleagues found CBT superior to dynamic psychotherapy delivered in a groups.[
33] There is simply little in this literature to warrant a designation of efficacious or specific.
On the whole, although there is still not compelling evidence speaking to the efficacy of dynamic psychotherapy, it would be premature to conclude that it is not efficacious solely on the basis of early trials by advocates of other approaches. More recent studies by investigators who have an investment in and expertise with the approach do offer some limited support and meta-analyses that aggregate across studies regardless of quality find it no less efficacious than alternative types of psychotherapies.
10,
11 Although none of the studies in the literature provide strong support for the approach relative to either medications or alternative psychotherapies, one study does suggest an advantage over routine primary care[
21] and two others suggest that it can enhance the efficacy of medications on at least some measures[
22] and for at least some patients.[
24,
25] Yet another recent study suggests that its effect may build over time[
27] and protect against subsequent recurrence.[
28] It seems fair to say that dynamic psychotherapy is possibly efficacious with respect to acute response and the prevention of subsequent relapse/recurrence.
Interpersonal Psychotherapy Interpersonal psychotherapy (IPT) springs from dynamic roots, but draws on attachment theory and theoretical revisions that focus on interpersonal relationships.[
34] It is more structured than dynamic psychotherapy (but less so than cognitive or behavioral approaches) and focuses on current interpersonal difficulties rather than childhood recollections or the therapeutic relationship.[
35]
IPT has fared well in a series of controlled trials in fully clinical populations. Klerman and colleagues found that patients treated to remission with the combination of IPT and medications were no more likely to relapse if continued on IPT alone than if continued on medications[
36] and patients treated with IPT showed a greater (if somewhat delayed) improvement in interpersonal functioning than did patients treated with medications alone.[
37] In a subsequent study, Weissman and colleagues found that outpatients treated with IPT did as well as patients treated with medications and better than patients provided with treatment-on-demand in terms of symptom reduction and that patients treated with combined treatment did better still.[
38] Drugs produced more rapid change,[
39] but IPT again had a delayed effect on interpersonal functioning.[
40] This study speaks to the efficacy of IPT in the reduction of acute symptoms.
IPT also fared well in the placebo-controlled NIMH Treatment of Depression Collaborative Research Project (TDCRP), one of the largest and most influential studies of its time.[
41] Among more severely depressed patients, both IPT and drugs outperformed pill-placebo, whereas CBT did not; no differences were evident among less severely depressed patients or in the sample as a whole.[
42] Once again, drugs produced faster change than IPT, which showed more change later in treatment.[
43] IPT also reduced depressive symptoms and improved social adjustment in women suffering from postpartum depression over wait list in one study[
44] and was superior to didactic parent education in a sample of pregnant women with MDD in another.[
45] This last study and the TDCRP suggest that IPT is efficacious and specific in the treatment of MDD.
Subsequent studies have not been as supportive. A study conducted in New Zealand found that IPT was less efficacious than CT for patients with more severe depression[
46] or perhaps personality disorders.[
47] Similarly, a recent Canadian trial found IPT less efficacious than medications.[
48] Internal analyses indicated that IPT did particularly poorly with patients high on self-criticism. Although efficacious and specific according to Chambless and Hollon's (1998) criteria,[
7] findings with respect to IPT are no longer as consistent as they once were when only advocates conducted trials on the approach.
Studies in special populations also are worthy of note. IPT was as efficacious as drugs (imipramine) plus supportive therapy and more efficacious than either CT or supportive psychotherapy alone in the treatment of depression in a sample of HIV-positive patients; this study would speak to both efficacy and specificity except that only about half the sample met criteria for MDD.[
49] Bolton and colleagues found that indigenous nonprofessionals in rural Uganda could be trained to provide group IPT to fellow villagers that reduced rates of depression and improved functioning[
50] and that these differences were sustained across a six month follow-up.[
51] IPT was as efficacious as medications (if somewhat slower acting) and more efficacious than treatment-as-usual in one study in a primary care setting,[
52] although training physicians to provide IPT-based education did little to enhance response to medication in a small general practice sample in another.[
53] Adding IPT enhanced response to medication in an inpatient sample,[
54] including patients with chronic depression,[
55] and there were indications that these differences extended beyond the end of treatment. Finally, a version of the approach adapted for depressed mothers of offspring with psychiatric disorders (IPT-MOMS) was more efficacious than treatment-as-usual in reducing depression in both the mothers and their offspring.[
56] On the other hand, Reynolds and colleagues found that IPT did not differ from pill-placebo and was less efficacious than medication in reducing acute distress in a “young” geriatric sample (aged 50 and above) with a history of recent bereavement[
57] and no better than usual care with respect to rates of remission or measures of symptom change in another study on a geriatric primary care sample aged 55 and over, although it did reduce the proportion of patients who continued to meet criteria for depression at posttreatment.[
58]
Frank and colleagues found monthly maintenance IPT superior to withdrawal onto pill-placebo in a sample of recurrent patients treated to recovery with combined treatment, but maintenance medication (imipramine) was more efficacious still and combined treatment did nothing to improve on medications alone.[
59] Maintenance IPT was most efficacious when the sessions maintained a high level of interpersonal focus suggesting the importance of quality of implementation.[
60] When this design was replicated in that same setting in a “young” geriatric sample (mainly 60 to 75 years of age), both maintenance IPT and maintenance medications were superior to pill-placebo, with combined treatment best of all.[
61] These studies suggest that maintenance IPT is possibly efficacious for the prevention of recurrence, although a subsequent replication found maintenance IPT no more efficacious than pill-placebo and less efficacious than maintenance medication in the treatment of depression in an older geriatric sample aged 70 and above.[
62] IPT was protective of cognitively impaired unmedicated elders.[
63]
Although negative findings do exist,[
46-
48] IPT appears to be efficacious and specific in the reduction of acute distress[
42,
45] and may forestall both relapse and recurrence so long as it is continued or maintained, although perhaps not so well as medications.[
36,
59,
61] In some studies, combined treatment improved on drugs alone,[
38,
54] although that was not always the case. There also were indications that IPT has a delayed effect on interpersonal skills and relationship quality that builds over time.[
37,
40] This represents a specific benefit of IPT and may enhance its value as an adjunct to medications. It also appears to be efficacious in the treatment of perinatal depression.[
44,
45] This is important since pregnant and lactating women may have special reasons to prefer not to be on medication. Recent trials by investigators outside of the core IPT group have not been as uniformly supportive as earlier trials by advocates for the intervention, but the efficacy of the approach appears to be well established when implemented by well-trained therapists.
Cognitive Behavior Therapy The cognitive behavioral therapies (CBT), of which cognitive therapy (CT) is the most widely practiced variant, assume that negative beliefs and maladaptive information processing contribute to the onset and maintenance of depression. These interventions seek to produce change by teaching patients to evaluate the accuracy of their beliefs (or the relation between their thoughts and feelings in the newer meditation-based approaches), often by using their own behaviors to test their beliefs. CBT has been tested extensively and typically found to be superior to minimal treatment controls and at least as efficacious as other empirically supported interventions.[
64] Nonetheless, questions remain as to how it compares to drugs in the treatment of severe depression.[
65]
Early studies suggested that CT might be superior to drugs, but often implemented medications in a less than adequate fashion.[
66,
67] The same appeared to be the case in a later trial that found both CT and relaxation training (included as a nonspecific control) superior to tricyclic ADM in a very small sample with an uncharacteristically poor response to medication.[
68] These studies could be taken as support for the specific efficacy of CT since even inadequately implemented medication conditions should have controlled for nonspecific factors, but we are not prepared to go so far. Subsequent studies suggested that CT and drugs are comparable in efficacy when each is adequately implemented[
69,
70] and an even more recent study suggests that the same may be true for rational emotive behavior therapy (REBT),[
71] with either type of psychotherapy more cost-effective.[
72] As previously described, CT was less efficacious than either IPT or medications and no more efficacious than pill-placebo in the treatment of severe depression in the TDCRP, the largest and best controlled study of its time,[
41,
42] but response to treatment varied across sites and CT did as well as medication in the site with more experienced cognitive therapists.[
73] DeRubeis and colleagues reanalyzed individual response data on severely depressed patients from the studies just cited and found no differences between CT and drugs across the pooled samples.[
74] However, we are reluctant to base a claim of efficacy solely on equivalence to an established standard.[
7]
A more recent trial by Jarrett and colleagues found CT as efficacious as medications and superior to pill-placebo in patients with atypical depression[
75] and a subsequent study by DeRubeis and colleagues essentially replicated these findings among patients with more severe depressions.[
76] These trials are important because they demonstrate that CT can do as well as medications in fully clinical samples that respond to medications.[
77] The fact that CT was superior to pill-placebo in each speaks to both efficacy and specificity. An even more recent trial from Iran found CBT superior to medications and both superior to a no treatment control in a sample of depressed women with fertility problems.[
78]
However, the efficacy of CT may be moderated both by patient characteristics and therapist experience. In the study by DeRubeis and colleagues,[
76] patients with Axis II disorders did better on medications than they did in CT, whereas patients free from such disorders showed the opposite pattern.[
79] Moreover, CT was less efficacious than medications at the site with less experienced cognitive therapists[
76] (see also the study by Bright and colleagues).[
80] This is reminiscent of earlier findings from the TDCRP and consistent with the poor showing by somewhat less experienced cognitive therapists with more severe and complicated patients in a placebo-controlled comparison to medication or behavioral activation described in a subsequent section.[
81] Similarly, Bagby and colleagues found that patients with higher neuroticism scores did better on medications than they did in CBT in a study that otherwise found no main effect for treatment.[
82] On the other hand, a recent trial from New Zealand found that CT was more efficacious than IPT among patients with more severe depression[
46] or Axis II disorders.[
47] Although the therapists in that trial were all experienced, it is not clear just how expert they were with either treatment. These findings suggest that CT's efficacy with more severe and complicated patients may vary across studies and depend in part on therapist experience.
Another recent study found CT as efficacious as drugs in recurrent patients[
83] and adding CT typically enhanced the efficacy of medication treatment in inpatient samples.[
84,
85] Studies in primary care settings have found that adding CT typically enhances the efficacy of usual care[
86,
87] and did so in one study over and above the benefits provided by a contact control,[
88] although that has not always been the case.[
89] CT was as efficacious as medications and superior to community referral in a sample of mostly low-income minority women with MDD[
90] and its effects extended across a one-year follow-up.[
91] CBT was superior to treatment-as-usual (TAU) among severely depressed outpatients.[
92] In general, these findings are consistent with the notion that CBT is efficacious (if not necessarily specific) in the treatment of MDD.
Patients treated to remission with CT are less likely to relapse following treatment termination than patients treated to remission with drugs alone;[
93-
95] the magnitude of this effect is at least as great as keeping patients on continuation medication[
96] and superior to placebo withdrawal.[
97,
98] Only the TDCRP failed to find an enduring effect for prior CT.[
99] Moreover, these effects may extend to the prevention of recurrence, although comparisons to placebo controls typically do not extend beyond the period of risk for relapse.[
97,
98] These studies indicate that CT has an enduring effect that is both efficacious and specific in the prevention of relapse and efficacious with respect to recurrence.
Studies also have shown that CBT can be added following initial medication treatment to prevent subsequent symptom return and that this enduring effect can last for up to several years.[
100-
103] Providing group CBT to remitted patients reduced risk for subsequent relapse or recurrence among patients with more prior episodes[
104] and a similar moderated effect was found for acute CBT followed by brief psychoeducation (but not psychoeducation alone) for patients with four or more prior episodes.[
105] An earlier trial by this latter group found no differences between a depression recurrence prevention program with or without CBT relative to usual care in a general practice sample.[
106] The only studies that failed to find an enduring effect for CBT provided following remission compared it to continuation medication.[
107,
108]
Teasdale and colleagues have shown in two studies that training in mindfulness-based cognitive therapy (MBCT) can reduce risk for relapse or recurrence in patients initially treated with medications.[
109,
110] MBCT had its strongest preventive effects on patients with three or more prior episodes, a pattern of moderation that suggests that it may work through different mechanisms than standard CBT. A subsequent trial found MBCT more effective than maintenance medication in reducing residual depressive symptoms and improving quality of life; 75% of the MBCT patients in that trial were able to discontinue medications.[
111] Differences in rates of relapse/recurrence favored MBCT but were not significant. Given that multiple sites were involved in one of the trials,[
109] we consider MBCT to be efficacious in the prevention of relapse/recurrence.[
110]
Combined treatment typically retains the specific benefits of either modality alone (more rapid or robust change for drugs versus more enduring change for CT), but differences in acute response relative to either monotherapy were not believed to be all that large.[
112,
113] However, more recent studies suggest a larger incremental effect; d=.25 relative to psychotherapy alone with an NNT = 7.14[
114] and d=.31 relative to medications alone with an NNT of 5.75.[
115] It was a recent trial by Keller and colleagues that renewed interest in combined treatment.[
116] In that study, the combination of drugs (nefazodone) and a novel cognitive behavioral analysis system for psychotherapy (CBASP) targeted at interpersonal change and incorporating dynamic elements was more efficacious than either monotherapy in patients with chronic depression. Drugs worked best early on, while CBASP worked better late, and combined treatment retained the temporal advantages of each. This study suggests that CBASP is possibly efficacious in the treatment of chronic depression and there was no indication that meeting criteria for a personality disorder did anything to moderate the effects of treatment.[
117] Continuing CBASP after recovery reduced risk for recurrence,[
118] as does continuing CT with respect to relapse and recurrence.[
119] These trials suggested that maintenance CBASP is possibly efficacious in the prevention of recurrence and that continuation CT is possibly efficacious in the prevention of relapse and recurrence. However, a subsequent effort at replication by several of the same investigators found that augmentation with CBASP was no more efficacious than individualized pharmacotherapy alone in chronic patients who failed to respond to three months of initial medication treatment.[
120]
CBT was superior to sleep hygiene with respect to remission in both depression and insomnia when each was added to medication in the treatment of patients diagnosed with both MDD and insomnia[
121] and superior to treatment-as-usual (often involving antidepressant medications) in the treatment of depression following coronary bypass surgery (especially among the two-thirds of the sample that met criteria for MDD).[
122] Dozois and colleagues found that adding CT did little to enhance the efficacy of algorithm-driven pharmacotherapy in a small sample but did produce greater change in underlying cognitive structure.[
123] Thompson and colleagues found that combined treatment was superior to medication alone in a geriatric sample with CBT alone intermediate and different from neither.[
124] Laidlaw and colleagues found that geriatric patients treated with CBT alone were less likely to meet criterion for MDD than patients treated with treatment-as-usual including medication in a general practice setting.[
125]
Cognitive therapy did not differ from medication as a second-step treatment for patients who did not respond to citalopram in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) project, although augmentation with medication resulted in significantly more rapid remission than augmentation with CT.[
126] Rohan found CT comparable to light therapy and both superior to a wait list control in a sample of patients with seasonal affective disorder.[
127] Strauman and colleagues found no overall differences between CT and their preferred self-system therapy (SST), although the latter was superior to CT for some patients.[
128] Two studies have found that computer-assisted CT was as efficacious as therapist-administered CT with both superior to a wait list control.[
129,
130] Finally, as previously noted, a recent trial found REBT comparable to either CT or fluoxetine in the treatment of MDD and superior to continuation medication at a cross-sectional six month follow-up.[
71] We are reluctant to categorize REBT as possibly efficacious with respect to acute response on the basis of null findings in a single trial or with respect to the prevention of relapse on the basis of cross-sectional assessment (since patients had ample time to relapse and subsequently remit in the interim) but note that the findings for REBT in this study were promising and merit further consideration.
On the whole, it appears that CBT (and especially CT) is as efficacious and specific as medications in the treatment of MDD,[
75,
76] although therapist competence may be an important moderating factor with more severe or complicated patients.[
42,
81] Early indications of general superiority to medications[
66-
68] or any specific inferiority among more severely depressed patients (the latter from the TDCRP) have not held up in subsequent trials in which each modality was adequately implemented.[
69-
71,
75,
76,
83] There are consistent indications that CT has an enduring effect that protects against subsequent relapse and possibly recurrence regardless of when it is applied[
93-
98,
100-
105] and indications that the same might be the case for MBCT.[
109-
111] This is especially important given the recurrent nature of depression and the fact that medications appear to have no lasting effect following treatment termination. Continuation/maintenance CT has been found to reduce risk for relapse/recurrence in MDD[
119] and CBASP has been found to reduce acute distress[
116] and subsequent recurrence when maintained in chronic MDD[
118] in single studies and can be said to be possibly efficacious.
Behavior Therapy Behavioral interventions include contextual approaches based on functional analyses (contingency management and behavioral activation), social skills training, self-control therapy, problem-solving therapy, and behavioral marital therapy. Although these approaches have not been tested as extensively as CBT, they have generally done well in controlled trials.[
4] BT typically has been found to be superior to minimal treatment and at least as efficacious as other interventions, but studies in fully clinical populations have been few and comparison treatments sometimes suspect.
As previously described, McLean and Hakstian found a modest advantage for contingency management relative to drugs alone or brief dynamic psychotherapy,[
14] but dosages were low and the dynamic intervention questionable. Hersen and colleagues found no differences between social skills training (SST) with or without medications and either amitriptyline alone or brief dynamic psychotherapy when each was adequately implemented.[
17] Kornblith and colleagues found no differences between self-control therapy (SCT) and dynamic therapy,[
18] whereas the addition of self-control therapy (SCT) enhanced response relative to usual care in a day-treatment program.[
131]
Nezu and colleagues found problem-solving therapy (PST) superior to nonspecific or wait list controls in two studies with recruited adults,[
132,
133] as did Arean and colleagues in a geriatric sample.[
134] Mynors-Wallis and colleagues found PST comparable to drugs and superior to placebo in one study in a general practice sample[
135] and comparable to medications in another.[
136] A large multicenter randomized trial by Dowrick and colleagues found PST superior to an assessment only control in reducing levels of depression in participants across five European countries.[
137] These studies suggest in aggregate that PST is efficacious and possibly specific in the treatment of MDD. The fact that only one used a pill-placebo control in a bona-fide clinical sample reduces our confidence in this conclusion somewhat since nonspecific psychological controls are hard to implement in a convincing fashion and recruited samples reduce generalizability.
Behavior marital therapy (BMT) was as efficacious as CBT and superior to a wait list control in the treatment of depression in couples with marital distress.[
138,
139] A second study found BMT as efficacious as CBT in reducing depression for women with marital distress, but less efficacious than CBT for women without marital problems[
140,
141] and a third found no differences between the two on measures of depression.[
142] These studies fall short of suggesting that BMT is possibly efficacious in the treatment of MDD since the first recruited patients with
either major depression
or dysthymia and the others had small sample sizes that limited the conclusions one could draw on the basis of null findings.[
7] Nonetheless, BMT was more efficacious than CT in reducing marital distress in all three studies. A recent trial found coping-oriented couples therapy (COCT) that included many elements of behavioral marital therapy comparable to either CT or IPT in terms of the reduction of depressive symptoms but no better with respect to the resolution of marital distress.[
143] However, this study suffered from a small sample size.
Despite these early successes, interest in BT stagnated before Jacobson and colleagues found that the behavioral activation component of CT produced as much change during acute treatment as the full treatment package,[
144] with no differences in rates of subsequent relapse.[
145] These findings were so unexpected that they led Jacobson and colleagues to conduct a placebo-controlled trial to compare a more comprehensive contextual version of behavioral activation (BA) against both CT alone and medications. In that trial, Dimidjian and colleagues found that BA and medications were comparably efficacious and each was superior to CT or pill-placebo in the treatment of more severely depressed patients.[
81] Moreover, Dobson and colleagues found that among remitted patients, those previously treated with BA were no more likely to relapse following treatment termination than patients previously treated with CT or than patients kept on continuation medications and showed a marginal advantage relative to medication withdrawal with respect to both relapse and recurrence.[
98] Had the effect been fully significant or the sample larger we would have been tempted to suggest that BA has an enduring effect with respect to the prevention of subsequent relapse or recurrence, but we are not prepared to go quite that far as yet. Nonetheless, these findings are promising in that respect and deserve to be followed up in future studies.
The fact that prior exposure to CT showed an enduring effect in Dobson and colleagues relative to withdrawal onto a pill-placebo for previously medicated patients goes along with findings from Hollon and colleagues to establish the specific efficacy of prior CT with respect to the prevention of subsequent relapse.[
97,
98] CT's poor performance with more severe and complicated patients was reminiscent of earlier findings from the TDCRP and may reflect the difficulties inherent when less experienced cognitive therapists try to implement a complicated treatment in a time-limited fashion.[
146] That being said it is worth noting that BA encountered no such difficulties. Given that BA appears to be less complex and easier to learn than CT, this study has generated renewed interest in behavior therapy as a cost-effective alternative to medication in the treatment of MDD and another recent trial found behavioral activation superior to supportive psychotherapy in an inpatient sample.[
147] Combined with the results from the earlier study by McLean and Hakstian,[
14] these studies indicate that behavior activation is efficacious and specific in the treatment of MDD.
On the whole, these studies suggest that BT is efficacious and specific in the treatment of MDD. The evidence is most compelling for the contextual approaches (BA and contingency management) that have been tested against other efficacious interventions in fully clinical samples. [
14,
81,
147] PST also met our criteria for being efficacious and specific, although the supporting studies come from recruited volunteers[
132,
134] or general practice samples.[
135] BMT falls short of being possibly efficacious with respect to depression (although it is clearly efficacious for marital distress) since outcomes are mixed at best and the samples too small for equivalence to support efficacy.[
138-
143]