Reviews and Overviews

A Multidimensional Meta-Analysis of Psychotherapy for PTSD Rebekah Bradley, Ph.D. Jamelle Greene, M.A. Eric Russ, B.A. Lissa Dutra, M.A. Drew Westen, Ph.D.

Objective: The authors present a multidimensional meta-analysis of studies published between 1980 and 2003 on psychotherapy for PTSD. Method: Data on variables not previously meta-analyzed such as inclusion and exclusion criteria and rates, recovery and improvement rates, and follow-up data were examined. Results: Results suggest that psychotherapy for PTSD leads to a large initial improvement from baseline. More than half of patients who complete treatment with various forms of cognitive behavior therapy or eye movement desensitization and reprocessing improve. Reporting of metrics other than effect size provides a somewhat more nuanced account of outcome and generalizability. Conclusions: The majority of patients treated with psychotherapy for PTSD in

randomized trials recover or improve, rendering these approaches some of the most effective psychosocial treatments devised to date. Several caveats, however, are important in applying these findings to patients treated in the community. Exclusion criteria and failure to address polysymptomatic presentations render generalizability to the population of PTSD patients indeterminate. The majority of patients posttreatment continue to have substantial residual symptoms, and follow-up data beyond very brief intervals have been largely absent. Future research intended to generalize to patients in practice should avoid exclusion criteria other than those a sensible clinician would impose in practice (e.g., schizophrenia), should avoid wait-list and other relatively inert control conditions, and should follow patients through at least 2 years. (Am J Psychiatry 2005; 162:214–227)

P

osttraumatic stress disorder (PTSD) is one of the most prevalent axis I disorders (1) for which psychotherapy is widely practiced. The psychotherapy research literature has focused primarily on cognitive behavior therapy approaches (particularly exposure and cognitive restructuring) and eye movement desensitization and reprocessing. Exposure therapy includes confrontation of memories of the trauma or cues (“triggers”) related to the traumatic event. Other cognitive behavior therapy approaches focus on developing skills for anxiety management or challenging distorted cognitions. Another treatment approach is eye movement desensitization and reprocessing (2), in which the patient is asked to develop a mental image of a traumatic event and related negative cognitions while tracking a bilateral stimulus. The mechanisms of action are largely unknown, although likely possibilities include exposure, other cognitive behavior therapy-like interventions (e.g., choosing and altering a negative belief about the self ), and accessing of associative networks as in psychodynamic psychotherapy (3, 4). Reviews and metaanalyses have supported the efficacy of psychotherapy for PTSD, particularly cognitive behavior therapy and, more recently, eye movement desensitization and reprocessing (5–9). Although case studies have suggested the potential utility of other therapeutic approaches, such as psychody-

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namic and humanistic/experiential psychotherapy, research is not available to draw strong conclusions. Although the short-term treatments tested in clinical trials (primarily cognitive behavior therapy) are clearly effective in reducing PTSD symptoms, research has yet to delineate clearly which patients are most likely to respond. Research on prognostic factors is limited, with different studies often finding different predictors (10–14). Of particular interest from a clinical standpoint is comorbidity, which is the rule rather than the exception in PTSD. Studying PTSD in an urban population, Breslau and colleagues (15) reported that 83% of individuals with PTSD met criteria for one or more other disorders. The most common comorbid conditions include depression, substance abuse, and other anxiety disorders (1, 15). Patients with PTSD are also frequently comorbid for axis II disorders and vice versa. For example, Yen et al. (16) found a 35% lifetime prevalence of PTSD among patients with personality disorders who reported any traumatic event and also found an association between severity of traumatic exposure and severity of personality disorder. Despite these high rates of comorbidity, empirical research addressing treatment effectiveness for patients presenting with specific patterns of comorbidity is sparse. Am J Psychiatry 162:2, February 2005

BRADLEY, GREENE, RUSS, ET AL.

Goal of This Study

Method

In this study we present a multidimensional meta-analysis (17, 18) of data from controlled trials of psychotherapy for PTSD, with the goal of describing a range of indices that bear on efficacy and generalizability, many of which have not previously been subjected to meta-analytic aggregation. A multidimensional meta-analysis presents, in addition to effect size, a range of statistics bearing on clinical utility and external validity that can be important in assessing the strengths and limitations of treatments of psychiatric disorders but are generally omitted from metaanalytic assessments of treatments. First, although most treatment studies attempt to maximize internal validity through their screening processes and inclusion/exclusion criteria, these decisions can affect external validity or generalizability. Thus, we aggregated data on both inclusion/exclusion criteria and patient exclusion rates. Second, no single index of outcome provides a comprehensive description of the effects of a treatment; a more nuanced portrait may require presentation of multiple metrics. Although effect size provides a crucial index of the effect an average patient can expect to achieve, it does not yield information on response variability, notably the proportion of patients who recover or experience clinically significant improvement. Thus, in addition to effect size, two additional indices are included in this meta-analysis: recovery rate and improvement rate. In calculating improvement and recovery rates, however, of particular importance is the denominator one chooses, i.e., the proportion improved or recovered out of what group of patients? The most liberal estimate uses as the denominator the number of study completers, eliminating patients who dropped out of treatment. A more conservative estimate uses the number of patients who actually began treatment (i.e., the intent-to-treat study group). Neither metric is more definitive than the other; consumers of research can draw the most accurate conclusions if researchers report both completer and intent-to-treat analyses (19). Because the completer/intent-to-treat distinction is orthogonal to the distinction between recovery and clinically significant improvement, we present four metrics: recovery rate among study completers, recovery rate for the intent-to-treat study group, improvement rate among study completers, and improvement rate for the intent-to-treat study group. Another variable that bears on efficacy is mean posttreatment symptom level. A treatment could lead to substantial improvement in most patients but nevertheless leave most patients highly symptomatic. A final variable of crucial importance is sustained efficacy over time. A treatment that produces an initial response, or a response that holds for 3 to 6 months after termination, may or may not be an efficacious treatment for a disorder such as PTSD, which tends to be longstanding.

Selection of Studies

Am J Psychiatry 162:2, February 2005

To maximize the likelihood of obtaining all relevant published research, we used a three-phase search process. First, we identified studies using a manual search of 19 high-quality, high-impact journals that routinely publish efficacy research, including research on PTSD (e.g., The American Journal of Psychiatry, Journal of Consulting and Clinical Psychology). Next, we conducted an exhaustive computer search of PsychInfo and Medline, using the key words “PTSD” and “Posttraumatic.” Last, we manually reviewed prior meta-analyses and reviews for studies not obtained using the first two procedures. We included studies published in the years 1980–2003. Inclusion of only published studies (rather than unpublished, “filedrawer” studies [20]) in this study as in past reviews and metaanalyses means that the findings can only be generalized to published research and therefore could potentially inflate estimates of efficacy. We did this because our prior research using this method with other disorders has identified a number of limitations of the treatment literature we have meta-analyzed, leading to conclusions somewhat at odds with prior reviews. We thus wanted to reexamine data similar to those examined in prior reviews and meta-analyses, from which conclusions about efficacy and treatment of choice have been drawn, without the possibility that any findings reflect sample differences or biases on our part. To be included, we required studies to meet the following criteria. 1) The study had to test a specific psychotherapeutic treatment for PTSD for efficacy against a control condition, an alternative credible psychotherapeutic treatment, or a combination of two or more of the above (relaxation and biofeedback were included as control conditions, not as primary treatments tested, in accordance with the stated goals and theoretical descriptions of the treatments in the primary articles reviewed). 2) The study had to use a validated self-report measure of PTSD symptoms or a validated structured interview administered and scored by an evaluator blind to treatment condition. In studies reporting both a valid self-report measure and an interview assessment for which the evaluator was not blind, we used only the self-report data in our analyses. 3) The study had to be experimental in design, including random assignment of patients to condition and standardized treatment. 4) Enough patients had to be included to randomly assign 10 patients to each experimental group. We chose a priori to exclude studies with fewer than 10 patients per condition because of methodological concerns about studies that build in too little power to detect effects and because of concerns about maintaining the blind with such small Ns. 5) The study had to be reported in English. We excluded studies that reanalyzed data already included in the meta-analysis unless they provided new data. We included only studies that used adult patients and that examined treatment of PTSD proper (rather than acute stress disorder, preventive programs such as debriefing in the wake of a traumatic event, etc.). All decisions of this sort were made a priori, before examining any individual studies.

Procedure We assessed the following variables: number of participants, participant inclusion rate (out of those screened for participation), number of exclusion criteria, study completion rate, effect size (for both treatment versus control conditions and pre- versus posttreatment), rate of diagnostic change (i.e., patients no longer meeting criteria for PTSD), improvement rate (for study completers as well as the intent-to-treat study group), and mean posttreatment symptom level. We assessed the same variables at follow-up intervals of 6 months and beyond. Table 1 lists each study, each active and control condition, and the data we extracted and analyzed so that researchers can dihttp://ajp.psychiatryonline.org

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PSYCHOTHERAPY FOR PTSD TABLE 1. Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD Inclusion Rate (%)b

Study and Treatment Modalitya Brom et al. (21), 1989 Trauma desensitization1 Hypnotherapy5 Psychodynamic therapy5 Wait-list control condition7 Bryant et al. (22), 2003 Imaginal exposure1 Imaginal exposure plus cognitive restructuring2 Supportive counseling6 Carslon et al. (23), 1998 Eye movement desensitization and reprocessing4 Biofeedback-assisted relaxation6 Routine clinical care7 Cloitre et al. (24), 1992

Skills training plus exposure2 Minimal attention wait list7 Devilly and Spence (25), 1999 Trauma treatment protocol2 Eye movement desensitization and reprocessing4 Devilly et al. (26), 1998 Eye movement desensitization and reprocessing4 Eye movement desensitization and reprocessing–eye movements5 Wait-list control condition7 Fecteau and Nicki (27), 1999 Exposure1 Wait-list control condition7 Foa et al. (28), 1999

Trauma Type Mixed

Rate of Diagnostic Improvement Rate Change (%) (%) Number All Screened of Screened Subjects Completion Of Of Of Of Rate (%) Subjects Subjects With PTSD Assigned Completed Assigned Completed 100 — — — — — — — 27 — — 87 — — — — 25 — — 86 — — — — 25 — — 86 — — — — 23 — — 100 — — — —

Assault, motor vehicle accident

Combat

Childhood sexual abuse, childhood physical abuse

Mixed

Combat

Motor vehicle accident

Adult sexual assault, adult physical assault

Exposure1 Stress inoculation training3 Combined prolonged exposure and stress inoculation training 2 Wait-list control condition7

45

68

—

—

—

—

—

—

15 15

— —

— —

75 75

50 65

67 87

15 40

30 60

15 34 10

— 74 —

— — —

83 — 100

33 — 70c

40 — 70

0 — —

0 — —

12

—

—

92

15

17

—

—

12 46

— 56

— 75

100 —

— —

— —

— —

— —

22

—

—

71

55

77

32

46

24

—

—

89

22

25

4

4

53

—

—

—

—

—

—

—

12

—

—

80

47

58

60

75

41

—

—

65

18

27

18

27

41 12

— —

— —

— 68

— —

— —

— 42

— 62

13

—

—

75

—

—

31

42

16

—

—

63

—

—

6

10

20

86

96

—

—

—

10 10

— —

— —

83 91

42 0

50 0

67 18

80 20

79

82

—

—

—

—

—

—

23 19

— —

— —

92 73

60 42

65 58

52 31

57 42

22

—

—

73

40

54

27

36

15

—

—

100

0

0

0

0 (continued)

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Am J Psychiatry 162:2, February 2005

BRADLEY, GREENE, RUSS, ET AL. TABLE 1. Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD (continued) Inclusion Rate (%)b

Study and Treatment Modalitya Foa et al. (29), 1991 Prolonged exposure1 Stress inoculation training3 Supportive counseling6 Wait-list control condition7 Gersons et al. (30), 2000 Brief eclectic psychotherapy5 Wait-list control condition7 Glynn et al. (31), 1999 Exposure1 Exposure plus family therapy5 Wait-list control condition7 Ironson et al. (32), 2002 Exposure1 Eye movement desensitization and reprocessing4 Keane et al. (33), 1989 Exposure1 Wait-list control condition7 Krakow et al. (34), 2001

Trauma Type Adult sexual assault

Rate of Diagnostic Improvement Rate Change (%) (%) Number All Screened of Screened Subjects Completion Of Of Of Of Rate (%) Subjects Subjects With PTSD Assigned Completed Assigned Completed 45 — — — — — — — 10 14

— —

— —

71 82

42 41

58 50

29 59

40 71

11 10

— —

— —

79 100

7 0

10 0

27 0

36 0

42 22

79 —

— —

— 100

— 91

— 91

— 77

— 77

20

—

—

100

50

50

15

15

36 12 11

— — —

— — —

— 100 65

— — —

— — —

— — —

— — —

13

—

—

100

—

—

—

—

19 9 10

— — —

— — —

— 75 100

— — —

— — —

— 33 90

— 44 90

24 11 13

— — —

— — —

— 100 100

— — —

— — —

— 63 —

— 63 —

Adult sexual assault, childhood sexual abuse

126

83

—

—

—

—

—

—

Imagery rehearsal3 Wait-list control condition7 Lee et al. (35), 2002 Stress inoculation training with prolonged exposure2 Eye movement desensitization and reprocessing4 Marcus et al. (36), 1997 Eye movement desensitization and reprocessing4 Standard care6 Marks et al. (37), 1998 Prolonged exposure1 Cognitive restructuring3 Exposure plus cognitive restructuring2 Relaxation6 Paunovic and Ost (38), 2001 Mixed Exposure1 Cognitive behavior therapy2 Resick et al. (39), 2002 Adult sexual assault, childhood sexual abuse Cognitive processing2 Exposure1 Minimal attention7

66 60

— —

— —

75 75

— —

— —

36 29

59 38

24 12

78 —

88 —

— 92

— 62

— 67

— 69

— 75

12

—

—

92

62

67

77

83

66 33

69 —

73 —

— 100

— 77

— 77

— —

— —

33 77 20 18 19

— 80 — — —

— — — — —

97 — 87 95 79

49 — 65 63 54

50 — 75 75 67

— — 44 32 25

— — 53 32 32

20 16 9 7

— 59 — —

— 74 — —

95 — 0.90 0.70

52 — — —

55 — — —

14 — — —

15 — — —

121

59

87

—

—

—

—

—

41 40 40

— — —

— — —

66 65 85

53 53 2

80 83 3

53 37 —

76 58 — (continued)

Police work

Combat

Combat

Am J Psychiatry 162:2, February 2005

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PSYCHOTHERAPY FOR PTSD TABLE 1. Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD (continued) Inclusion Rate (%)b

Study and Treatment Modalitya Rothbaum (40), 1997 Eye movement desensitization and reprocessing4 Wait-list control condition7 Schnurr et al. (41), 2003 Trauma-focused group psychotherapy2 Present-centered comparison treatment6 Tarrier et al. (42), 1999 Exposure1 Cognitive3 Taylor et al. (43), 2003 Exposure1 Eye movement desensitization and reprocessing4 Relaxation6 Vaughan et al. (44), 1994 Image habituation5 Eye movement desensitization and reprocessing4 Relaxation6 Wilson et al. (45, 46), 1995/ 1997 Eye movement desensitization and reprocessing4 Wait-list control condition7 Zlotnick et al. (47), 1997

Trauma Type Adult sexual assault

Rate of Diagnostic Improvement Rate Change (%) (%) Number All Screened of Screened Subjects Completion Of Of Of Of Rate (%) Subjects Subjects With PTSD Assigned Completed Assigned Completed 18 — — — — — — —

Combat

10

—

—

91

82

90

—

—

8

—

—

80

10

12

—

—

253 118

15 —

— —

— 66

— —

— —

— 45

— 49

75

—

—

43

38

135 Mixed Mixed

Crime

Mixed

Childhood sexual abuse

Affect management5 Wait-list control condition7

62 29 33 45 15 15

45 — — 37 — —

53 — — — — —

— 83 89 — 68 79

— 49 38 — 60 47

— 59 42 — 87 60

— 34 30 — 41d 32

— 41 33 — 60 40

15 36 13 12

— 35 — —

— — — —

79 — 100 100

32 — 63e 63

40 — 63 63

33 — — —

42 — — —

11 74

— 70

— 70

100 —

63 —

63 —

— —

— —

37

—

—

92

—

—

—

—

37

—

—

92

—

—

—

—

33

—

—

—

—

—

—

—

17 16

— —

— —

70 74

61 30

88 41

— —

— —

a

Subscripts represent the type of therapy that the condition was coded as for purposes of data analysis: 1=exposure, 2=cognitive behavior therapy plus exposure, 3=cognitive behavior therapy, 4=eye movement desensitization and reprocessing, 5=other treatment, 6=supportive control condition, 7=wait-list control condition. b Proportion of patients who did not drop out between screening and group assignment out of all subjects screened for study participation (all screened subjects) and out of those screened for study participation who met PTSD criteria (screened subjects with PTSD). c Data are from 3-month follow-up evaluation because diagnostic data were not gathered at posttest. Although the raters were not blind at 3month follow-up assessment, a subset of patients were rated by blind raters at 9-month follow-up and their ratings were similar to those at 3-month follow-up. d Represents the average improvement rate for reexperiencing, avoidance, and hyperarousal domains of the Clinician-Administered PTSD Scale. e At entry to this study all patients met DSM-II-R criteria B and D for PTSD, but 22% failed to meet criterion A (avoidance/numbing). Thus these numbers represent the proportion of those initially diagnosed who no longer met criteria for PTSD.

Definition of Primary Variables

Number screened refers to the number of patients researchers reported screening for inclusion in the study (e.g., in initial interviews). In some cases, researchers first prescreened participants via phone and then in person. In these cases, we used the number screened rather than prescreened to maximize comparability to data from studies that did not report prescreening numbers. This produced a conservative estimate of number screened and exclusion rate because it does not include those initially screened out after a prescreening call (or those prescreened by referral sources, who are often aware of the kinds of patients researchers do and do not want included in a treatment study).

Number of participants refers to the number of people who actually began treatment (i.e., the number randomly assigned to any treatment condition who attended at least one session).

Number of exclusion criteria refers to the number of separate criteria used to exclude patients from a study. We did not count presence of psychosis, organic impairment, involvement in the

rectly assess our decisions and results. Decisions about how to code or define variables reflected our consistent efforts to 1) make methodological decisions prior to examining the data where possible, and 2) give the treatments under consideration the “benefit of the doubt” (18). For example, when researchers reported alternative values for the same analyses in the text and tables, we used the values that had the best results for the treatment. Two raters (each blind to the other’s ratings) coded each of the variables to ensure accuracy.

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Am J Psychiatry 162:2, February 2005

BRADLEY, GREENE, RUSS, ET AL. TABLE 2. Posttreatment Trauma Measure Scores and Improvement Effect Sizes Across PTSD Measures for Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD Posttreatment Score

Study and Treatment Modality Brom et al. (21), 1989 Trauma desensitization Hypnotherapy Psychodynamic therapy Wait-list control condition Bryant et al. (22), 2003 Imaginal exposure Imaginal exposure plus cognitive restructuring Supportive counseling Carslon et al. (23), 1998 Eye movement desensitization and reprocessing Biofeedback-assisted relaxation Routine clinical care Cloitre et al. (24), 1992 Skills training plus exposure Minimal attention wait list Devilly and Spence (25), 1999 Trauma treatment protocol Eye movement desensitization and reprocessing Devilly et al. (26), 1998 Eye movement desensitization and reprocessing Eye movement desensitization and reprocessing-eye movements Wait-list control condition Fecteau and Nicki (27), 1999 Exposure Wait-list control condition Foa et al. (28), 1999 Exposure Stress inoculation training Combined prolonged exposure and stress inoculation training Wait-list control condition Foa et al. (29), 1991 Prolonged exposure Stress inoculation training Supportive counseling Wait-list control condition Gersons et al. (30), 2000 Brief eclectic psychotherapy Wait-list control condition Glynn et al. (31), 1999 Exposure Exposure plus family therapy Wait-list control condition Ironson et al. (32), 2002 Exposure Eye movement desensitization and reprocessing Keane et al. (33), 1989 Exposure Wait-list control condition Krakow et al. (34), 2001 Imagery rehearsal Wait-list control condition Lee et al. (35), 2002 Stress inoculation training with prolonged exposure Eye movement desensitization and reprocessing Marcus et al. (36), 1997 Eye movement desensitization and reprocessing Standard care

Trauma Measuresa IES, STAI

PTSD Symptom Scale

Impact of Event Scale

Improvement Effect Size Treatment Pre- Versus Versus Control Posttreatment Condition

— — —

28.0 33.7 32.7 51.1

1.20 0.91 0.94 0.31

1.06 0.66 0.87 —

— — —

28.94 16.73 52.73

1.64 2.44 0.44

1.13 1.76 —

— — —

35.2 44.5 38.7

1.21 0.44 0.63

29.0 58.0

— —

1.78 0.49

1.16 —

14.42 24.64

20.75 35.64

1.51 0.75

— —

— —

— —

0.37 0.22

0.03/.32 –0.31

—

—

–0.01

—

— —

15.5 48.8

1.03 0.11

1.6 —

11.7 12.89 13.55

— — —

2.04 1.87 2.00

1.92 1.61 1.50

26.93

—

0.82

—

— — — —

— — — —

1.21 2.46 0.92 0.82

0.49/.29 1.45/1.22 0.20 —

— —

— —

1.30 0.44

0.66 —

— — —

— — —

0.50 0.52 0.07

0.80 0.52 —

15.78 9.10

— —

2.29 1.53

— —

— —

— —

0.59 0.47

0.23 —

17.19 25.26

— —

1.32 0.36

0.73 —

— —

30.25 23.17

1.25 1.68

— —

24.5 44.26

17.89 35.00

1.54 0.56

0.85 —

CAPS, IES, BDI, STAI

CAPSb, IES, MSCRP, BDI, STAI 0.56/1.44 –0.21 —

CAPS, PSS, STAI, BDI IES, PSS, MSCRP, BDI, STAI MSCRP, BDI, STAI

CAPS, IES, BDI, BAI PSS, BDI, STAI

BDI, STAI, PTSD severityc

PTSD structured interview Positive symptoms, negative symptomsd

PSS, BDI MMPI-K CAPS, PSS IES, MMPI-K, BDI PSS, IES, BDI, STAI

(continued)

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PSYCHOTHERAPY FOR PTSD TABLE 2. Posttreatment Trauma Measure Scores and Improvement Effect Sizes Across PTSD Measures for Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD (continued) Posttreatment Score

Study and Treatment Modality Marks et al. (37), 1998 Prolonged exposure Cognitive restructuring Exposure plus cognitive restructuring Relaxation Paunovic and Ost (38), 2001 Exposure Cognitive behavior therapy Resick et al. (39), 2002 Cognitive processing Exposure Minimal attention Rothbaum (40), 1997 Eye movement desensitization and reprocessing Wait-list control condition Schnurr et al. (41), 2003 Trauma-focused group psychotherapy Present-centered comparison treatment Tarrier et al. (42), 1999 Exposure Cognitive Taylor et al. (43), 2003 Exposure Eye movement desensitization and reprocessing Relaxation Vaughan et al. (44), 1994 Image habituation Eye movement desensitization and reprocessing Relaxation Wilson et al. (45, 46), 1995/1997 Eye movement desensitization and reprocessing Wait-list control condition Zlotnick et al. (47), 1997 Affect management Wait-list control condition

Trauma Measuresa CAPS, IES, BDI

Improvement Effect Size

PTSD Symptom Scale

Impact of Event Scale

Pre- Versus Posttreatment

— — — —

22.0 25.0 21.0 34.0

1.4 1.65 1.5 0.34

1.30 0.79 1.00 —

18.1 16.8

25.6 17.3

2.56 1.98

— —

13.66 17.99 27.77

— — —

2.16 2.95 0.06

1.92 2.75 —

14.3 35.0

12.4 45.4

2.43 0.51

3.23 —

— —

— —

0.33 0.20

0.22 —

— —

31.28 37.52

0.91 0.98

— —

— — —

— — —

2.15 1.74 1.29

0.63 0.06 —

— — — — —

— — — 11.0 30.0

0.65 1.35 0.56 1.69 0.22

0.23 0.64

— —

— —

0.55 –0.07

0.99 —

Treatment Versus Control Condition

PSS, IES, BDI, STAI CAPS, PSS, BDI

PSS, IES, BDI, STAI CAPS, PTSD checklist CAPS, IES, Penn Inventory, BDI, BAI CAPS, BDI

PTSD structured interview, HDRS

1.19 —

DTS, CRPTSS

a

IES=Impact of Event Scale; STAI=State-Trait Anxiety Inventory; CAPS=Clinician-Administered PTSD Scale; BDI=Beck Depression Inventory; MSCRP=Mississippi Scale for Combat-Related PTSD; PSS=PTSD Symptom Scale; BAI=Beck Anxiety Inventory; MMPI-K=Keane’s PTSD scale from MMPI, HDRS=Hamilton Depression Rating Scale; DTS=Davidson Trauma Scale; CRPTSS=Crime-Related Post Traumatic Stress Scale. b Clinician-Administered PTSD Scale data collected by raters blind to treatment condition was collected only at 9-month follow-up assessment; therefore, it is not included in this assessment of effect size. c Based on structured interview of PTSD symptoms. d Authors created factor scores using Mississippi Scale for Combat-Related PTSD, Impact of Event Scale, and Clinician-Administered PTSD Scale.

legal system, or failure to meet criteria for PTSD in this number, given that these are criteria that would likely lead a clinician in everyday practice to refer the patient or apply a different treatment. Since researchers enumerated multiple exclusion criteria related to alcohol or drugs (e.g., drug abuse or dependence), we counted this as one exclusionary criterion to maximize comparability across studies. Determining the exact nature of the screening criteria was sometimes difficult because these criteria often included many unstated assumptions. Many studies offered broad exclusion criteria such as “major mental illness,” whereas others presented more precise lists. Thus, simply counting the number of screening criteria might not provide an accurate picture. As in prior meta-analyses (17, 18), we assigned highly generalized criteria (e.g., severe chronic preinjury mental health difficulties) a score equal to the highest number of specific exclusionary criteria in the sample plus one. Inclusion rate refers to the proportion of patients who were randomly assigned after surviving inclusion and exclusion criteria and attrition before the first treatment session.

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Effect size was calculated by using Cohen’s d with the following formula: ([mean1–mean2]/[SD12+SD22])/2. When means or standard deviations were not reported, where possible we calculated effect size from other data provided (20). For articles reporting effect sizes without reporting raw data, we relied on the effect sizes provided in the published report. Where data were provided only in graphic form, we interpolated. We calculated effect sizes for both pre- versus posttreatment and treatment versus control condition. In cases where both full-scale and subscale scores for a PTSD measure were reported, we used the full-scale score. If subscale data only were reported, we aggregated the scales. Where the investigators reported data on multiple measures of PTSD symptoms, we aggregated the effect sizes across measures. We present these effect sizes in Table 2. Posttreatment scores were analyzed by using the two most commonly used PTSD assessment instruments, the PTSD Symptom Scale (either the interview or self-report version) and the Impact of Event Scale. Am J Psychiatry 162:2, February 2005

BRADLEY, GREENE, RUSS, ET AL. TABLE 3. Inclusion and Completion Rates of Studies Included in a Multidimensional Meta-Analysis of Psychotherapy for PTSD Number of Participants (per group) Inclusion Rate of Screened Subjects Item All active treatments Exposure Cognitive behavior therapya Exposure plus cognitive Eye movement desensitization and reprocessing Wait-list control Supportive control a

Study Completion Rate

N 44 13 5 9

Mean 21.27 17.7 30.0 29.8

SD 18.74 9.6 21.4 34.5

N 16 7 4 7

Mean 68.9 67.7 76.8 72.6

SD 16.7 17.0 9.9 11.6

N 44 13 4 9

Mean 78.9 75.9 82.8 67.0

SD 28.7 25.2 9.3 26.1

10 15 8

16.2 21.1 31.5

10.1 14.3 42.44

6 8 7

60.5 73.6 64.0

19.3 11.1 20.0

10 15 8

88.7 89.9 87.5

13.4 12.1 9.6

Includes all forms of cognitive behavior therapy except exposure and eye movement desensitization and reprocessing.

Rate of diagnostic change is the proportion of patients who met diagnostic criteria for PTSD pretreatment but no longer met these criteria posttreatment. We calculated this variable for both study completers and the intent-to-treat study group. In the absence of agreed-upon standards for clinically meaningful improvement, as in prior studies, we calculated improvement rates (of patients entering as well as completing treatment) by relying on definitions for improvement used by the authors. Typical examples of criteria for improvement were PTSD Symptom Scale score