Longitudinal studies have shown that specific phobias have a variable course, with relative exacerbations and improvements in symptoms over time. These studies have found that persistence of specific phobia diagnosis was roughly 20% at 1- to 12-year follow-up (range 6% to 38%).[3]Stinson FS, Dawson DA, Chou SP, et al. The epidemiology of DSM-IV specific phobia in the USA: results from the National Epidemiologic Survey on Alcohol and Related Conditions. Psychol Med. 2007 Jul;37(7):1047-59.
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[114]Eaton WW, Anthony JC, Gallo J, et al. Natural history of diagnostic interview schedule/DSM-IV major depression: the Baltimore epidemiologic catchment area follow-up. Arch Gen Psychiatry. 1997 Nov;54(11):993-9.
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[115]Magee WJ, Eaton WW, Wittchen HU, et al. Agoraphobia, simple phobia, and social phobia in the National Comorbidity Survey. Arch Gen Psychiatry. 1996 Feb;53(2):159-68.
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[116]Trumpf J, Becker ES, Vriends N, et al. Rates and predictors of remission in young women with specific phobia: a prospective community study. J Anxiety Disord. 2009 Oct;23(7):958-64.
http://www.ncbi.nlm.nih.gov/pubmed/19604666?tool=bestpractice.com
Up to 90% of patients reach clinically significant levels of improvement after treatment with exposure therapy.[117]Grös DF, Antony MM. The assessment and treatment of specific phobias: a review. Curr Psychiatry Rep. 2006 Aug;8(4):298-303.
http://www.ncbi.nlm.nih.gov/pubmed/16879794?tool=bestpractice.com
[118]Antony MM, Barlow DH. Specific phobias. In: Barlow DH, ed. Anxiety and its disorders: the nature and treatment of anxiety and panic. 2nd ed. New York, NY: Guilford Press; 2002:380-417. Most treatment gains are maintained after 1 year of treatment; however, further research is required to determine longer-term outcomes.[55]Choy Y, Fyer AJ, Lipsitz JD. Treatment of specific phobia in adults. Clin Psychol Rev. 2007 Apr;27(3):266-86.
http://www.ncbi.nlm.nih.gov/pubmed/17112646?tool=bestpractice.com
The probability of relapse is most likely reduced by scheduling periodic "booster" sessions with a therapist and through continued practice of self-directed exposures.