A meta-analysis is a quantitative research procedure used to synthesize the results of many similar empirical studies on a topic of interest. A 12-step process for conducting a meta-analysis of counseling outcome research is presented, and the process is demonstrated using a small-scale application of eight published studies exploring the effects of cognitive–behavioral therapy on participants with posttraumatic stress disorder.
American Psychological Association. (2010). Publication manual of the American Psychological Association (6th ed.). Washington, DC: Author.
2.
BeckA. T.SteerR. A.BrownG. K. (1996). Manual for the Beck Depression Scale (2nd ed.). San Antonio, TX: Psychological Corporation.
3.
BeggC. B. (1994). Publication bias. In CooperH.HedgesL. V. (Eds.), The handbook of research synthesis (pp. 399–409). New York: Russell Sage Foundation.
4.
BushmanB. J.WellsG. L. (2001). Narrative impressions of literature: The availability bias and the corrective properties of meta-analytic approaches. Personality and Social Psychology Bulletin, 27, 1123–1130.
5.
ChanF.RosenthalD. A. (2006). Advanced research methodology in rehabilitation. Rehabilitation Counseling Bulletin, 49, 219–222.
6.
CohenJ. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Hillsdale, NJ: Erlbaum.
7.
ElvikR. (1998). Evaluating the statistical conclusion validity of weighted mean results in meta-analysis by analyzing funnel graph diagrams. Accident Analysis and Prevention, 30, 255–266.
8.
ErfordB. T. (2008). Research and evaluation in counseling. Boston: Houghton Mifflin / Lahaska Press.
9.
FanX. (2001). Statistical significance and effect size in education research: Two sides of a coin. Journal of Educational Research, 94, 275–282.
10.
*
FoaE. B.HembreeE. A.CahillS. P.RauchS. A. M.RiggsD. S.FeenyN. C. (2005). Randomized trial of prolonged exposure for posttraumatic stress disorder with and without cognitive restructuring: Outcome at academic and community clinics. Journal of Consulting and Clinical Psychology, 73, 953–964.
11.
GlassG. V.McGawB.SmithM. L. (1981). Meta-analysis in social research. Beverly Hills, CA: Sage.
12.
GreenS. B.SalkindN. J. (2004). Using SPSS for Windows and Macintosh: Analyzing and understanding (4th ed.). Upper Saddle River, NJ: Prentice Hall.
13.
GrissonR. J.KimJ. J. (2005). Effect sizes for research. Mahwah, NJ: Erlbaum.
14.
HedgesL. V.OlkinI. (1985). Statistical methods for meta-analysis. San Diego, CA: Academic Press.
15.
*
HigginsJ. P.ThompsonS. G.DeeksJ. J.AltmanD. G. (2003). Measuring inconsistency in meta-analyses. British Medical Journal, 327, 557–560.. doi: 10.1136/bmj.327.7414.557
16.
*
HintonD. E.PhamT.TranM.SafrenS. A.OttoM. W.PollackM. H. (2004). CBT for Vietnamese refugees with treatment-resistant PTSD and panic attacks: A pilot study. Journal of Traumatic Stress, 17, 429–433.
17.
HunterJ. E.SchmidtF. L. (2004). Methods of meta-analysis: Correcting error and bias in research findings (2nd ed.). Thousand Oaks, CA: Sage.
18.
KazdinA. E. (1999). The meanings and measurement of clinical significance. Journal of Consulting and Clinical Psychology, 67, 332–339.
19.
KirkR. (1996). Practical significance: A concept whose time has come. Educational and Psychological Measurement, 56, 746–759.
20.
KlineR. B. (2004). Beyond significance testing. Washington, DC: American Psychological Association.
21.
LipseyM. W.WilsonD. B. (1993). The efficacy of psychological, educational, and behavioral treatment: Confirmation from meta-analysis. American Psychologist, 48, 1181–1209.
22.
LipseyM. W.WilsonD. B. (2001). Practical meta-analysis. Thousand Oaks, CA: Sage.
23.
*
McDonaghA.FriedmanM.McHugoG.FordJ.SenguptaA.MueserK. (2005). Randomized trial of cognitive–behavioral therapy for chronic posttraumatic stress disorder in adult female survivors of child sexual abuse. Journal of Consulting and Clinical Psychology, 73, 515–524.
24.
*
MonsonC. M.SchnurrP. P.ResickP. A.FriedmanM. J.Young-XuY.StevensS. P. (2006). Cognitive processing therapy for veterans with military-related posttraumatic stress disorder. Journal of Consulting and Clinical Psychology, 74, 898–907.
25.
OrwinR. G. (1983). A fail-safe N for effect size in meta-analysis. Journal of Educational Statistics, 8, 157–159.
26.
RobertsJ. K.HensonR. K. (2002). Correction for bias in estimating effect sizes. Educational and Psychological Measurement, 62, 241–253.
27.
RosenthalR. (1991). Meta-analytic procedures for social research. Thousand Oaks, CA: Sage.
28.
RosenthalR. (1994). Statistically describing and combining studies. In CooperH.HedgesL. V. (Eds.), The handbook of research synthesis (pp. 231–244). New York: Russell Sage Foundation.
29.
*
ShooshtaryM. H.PanaghiL.MoghadamJ. A. (2008). Outcome of cognitive behavioral therapy in adolescents after natural disaster. Journal of Adolescent Health, 42, 466–472.
30.
*
SijbrandijM.OlffM.ReitsmaJ. B.CarlierI. V.de VriesM. H.GersonsB. P. R. (2007). Treatment of acute posttraumatic stress disorder with brief cognitive behavioral therapy: A randomized controlled trial. American Journal of Psychiatry, 164, 82–90.
31.
SinkC. A.StrohH. R. (2006). Practical significance: The use of effect sizes in school counseling research. Professional School Counseling, 9, 401–411.
32.
*
SmithP.YuleW.PerrinS.TranahT.DalgleishT.ClarkD. M. (2007). Cognitive–behavioral therapy for PTSD in children and adolescents: A preliminary randomized controlled trial. Journal of the American Academy of Child and Adolescent Psychiatry, 46, 1051–1061.
33.
ThompsonB. (2002). “Statistical,” “practical,” and “clinical”: How many kinds of significance do counselors need to consider?. Journal of Counseling and Development, 80, 64–71.
34.
ThompsonB. (2006). The role of effect sizes in contemporary research in counseling. Counseling and Values, 50, 176–186.
35.
Vacha-HaaseT.ThompsonB. (2004). How to estimate and interpret various effect sizes. Journal of Counseling and Psychology, 51, 473–481.
36.
*
van EmmerikA. A. P.KamphulusJ. H.EmmelkampP. M. G. (2008). Treating acute stress disorder and posttraumatic stress disorder with cognitive behavioral therapy or structured writing therapy: A randomized controlled trial. Psychotherapy and Psychosomatics, 77, 93–100.
37.
WangM. C.BushmanB. J. (1998). Integrating results through meta-analytic review using SAS software. Cary, NC: SAS Institute.