We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Comment & Response |

Very Small P Values—Reply

Sarah M. Hartz, MD, PhD1; Laura J. Bierut, MD1; Michele T. Pato, MD2
[+] Author Affiliations
1Department of Psychiatry, Washington University in St Louis, St Louis, Missouri
2University of Southern California, Los Angeles
JAMA Psychiatry. 2014;71(8):969. doi:10.1001/jamapsychiatry.2014.707.
Text Size: A A A
Published online


In Reply Our study showed that, among individuals with severe mental illness, the rates of tobacco, alcohol, and other substance use are dramatically higher than in the general population.1 The criticisms made by Knapp and Hayat highlight long-standing statistical controversies: effect size vs P value and proper adjustment for confounding variables.

Article InformationCorresponding Author: Sarah M. Hartz, MD, PhD, Department of Psychiatry, Washington University in St Louis, 660 S Euclid Ave, Campus Box 8134, St Louis, MO 63110 (hartzs@psychiatry.wustl.edu).

Conflict of Interest Disclosures: Dr Bierut is listed as an inventor on issued US patent 8,080,371, “Markers for Addiction,” covering the use of certain single-nucleotide polymorphisms in determining the diagnosis, prognosis, and treatment of addiction. No other disclosures were reported.

Funding/Support: This project was funded by National Institutes of Health grants U10 AA008401, UL1 RR024992, P01 CA089392, R01 MH085548, R01 MH085542, K08 DA062380-1, KL2 RR024994, and K01 DA025733 and American Cancer Society grant ACS IRG-58-010-54.

Role of the Sponsor: The funders had no role in the preparation, review, or approval of the manuscript, and the decision to submit the manuscript for publication.

Additional Information: This letter represents the views of the coauthors on the original manuscript including Carlos N. Pato, MD, PhD, Patricia Cavazos-Rehg, PhD, and Janet L. Sobell, PhD.


Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

First Page Preview

View Large
First page PDF preview





August 1, 2014
Thomas R. Knapp, EdD; Matthew J. Hayat, PhD
1University of Rochester, Rochester, New York
2Georgia State University, Atlanta
JAMA Psychiatry. 2014;71(8):968-969. doi:10.1001/jamapsychiatry.2014.546.
Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

0 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.

See Also...