The Number Needed to Benefit from Information (NNBI):
Proposal from a mixed methods study with practicing family physicians

Clinical vignettes: Mixed methods data display

This website presents detailed research findings to support the following paper: Pierre Pluye, Roland M Grad, Janique Johnson-Lafleur, Vera Granikov, Michael Shulha, Bernard Marlow, & Ivan Ricarte (2013). The Number Needed to Benefit from Information (NNBI): Proposal from a mixed methods research study with practicing family physicians. Annals of Family Medicine. 11(6):559-67. DOI: 10.1370/afm.1565. PMID: 24218380 [PubMed] Free full-text: http://www.annfammed.org/content/11/6/559.long

The following diagram organizes clinical vignettes by type of health outcome. Click on one of the outcome boxes to display the corresponding clinical vignettes. See the summary below for more information.

Vignettes paths
Legend (using items from the Information Assessment Method)
ACQUISITION (interviewee’s search objective)
To address a clinical question about a specific patient
To fulfill a personal educational objective
To satisfy curiosity or for personal interest
To look up something I had forgotten
To share information with a patient, their family, or home health aides
To exchange information with other health professionals (e.g., a colleague)
To manage aspects of patient care with other health professionals
COGNITION (cognitive impact of information on the interviewee)
Interviewee's practice was changed and improved
Interviewee learned something new
This information confirmed the interviewee did the right thing
The interviewee was reassured
They were was reminded of something they already knew
APPLICATION (interviewee’s information use)
The interviewee used this information to persuade the patient, or to persuade other health professionals to make a change
As a result of this information the interviewee managed this patient differently
The interviewee had several options for this patient or did not know what to do, and used this information to justify a choice
They thought they knew what to do, and used this information to be more certain about the patient management
They used this information to better understand a particular issue related to the patient
OUTCOMES (patient health benefits)
This information helped to improve the patient’s health status, functioning or resilience
This information helped to prevent a disease or worsening of disease for the patient
This information helped to avoid unnecessary or inappropriate treatment, diagnostic procedures, preventative interventions or a referral
This information helped to increase the patient’s satisfaction about a treatment, diagnostic procedure or preventative intervention
This information helped to increase the patient’s knowledge
Numbers in the diagram represent the number of cases.

Summary of the research study

Purpose:
To describe family physicians’ use of information from an electronic knowledge resource for answering clinical questions, and perception of subsequent patient health outcomes; and to estimate the Number Needed to Benefit from Information (NNBI), defined as the number of patients for whom clinical information was retrieved, for one to benefit.
Methods:
A mixed methods research study was conducted, combining quantitative longitudinal and qualitative research studies. Participants were 41 family physicians from primary care clinics across Canada, who were given access to one resource on handheld computer in 2008-2009. Outcome assessment: Using a validated method, participants rated their searches. Rated searches were examined during interviews guided by log-reports including ratings. Cases were defined as clearly described searches where clinical information was used for a specific patient. For each case, interviewees described information-related patient health outcomes. Mixed methods data analysis: Quantitative and qualitative data were merged into clinical vignettes. We then estimated the NNBI.
Results:
Participants rated 1,193 searches for information over an average of 86 days. In 715, the search objective was directly linked to a patient. Of those, 188 were considered cases. In 53 cases, participants associated the use of information with at least one patient health benefit. This suggested an NNBI of 14.
Conclusion:
This study describes patient health benefits arising from the use of information directly retrieved by practicing family physicians from one electronic knowledge resource. A low NNBI can be used to encourage clinicians to search for information more frequently when they feel the need.

Authors

Pierre Pluye, McGill University, Department of Family Medicine, Montreal, Canada,

Roland Grad, McGill University, Department of Family Medicine, Montreal, Canada

Janique Johnson-Lafleur, Information Technology Primary Care Research Group (ITPCRG), Montreal, Canada

Vera Granikov, Information Technology Primary Care Research Group (ITPCRG), Montreal, Canada

Michael Shulha, Information Technology Primary Care Research Group (ITPCRG), Montreal, Canada

Bernard Marlow, College of Family Physicians of Canada, Mississauga, Canada

Ivan Luiz Marques Ricarte, University of Campinas, School of Electrical and Computer Engineering, Campinas, Brazil

Contact: pierre.pluye@mcgill.ca