Concepts and Measures

Interpersonal processes of care are the social-psychological aspects of the patient-physician interaction.  These important components of quality of care may help explain disparities in health between minority patients and their counterparts.  We have developed conceptual frameworks of interpersonal processes of care and patient-reported surveys to measure these processes, both to reflect the experiences of persons of lower socioeconomic status (SES) and racial/ethnic minority groups.  This effort was one of the first to assess patient’s actual experiences of care (what happened during their health care visits) as opposed to their satisfaction with those experiences.  Our work was done in two phases.

Phase One: We developed a comprehensive framework of concepts of interpersonal processes of care, based on an extensive literature review and formative research with minority patients, as well as a review of existing quality of care and satisfaction surveys.  We developed a survey, in English and Spanish, to reflect the concepts, administered it to a sample of ethnically diverse public hospital patients, and evaluated its psychometric properties.  A final 41-item survey confirmed the framework. 

• Citation: Stewart AL, Nápoles-Springer A, Pérez-Stable EJ, Posner S, Bindman AB, Pinderhughes HL, and Washington AE, Interpersonal processes of care in diverse populations.  The Milbank Quarterly. 77:305-39, 1999. PMCID: PMC2751132

Phase Two: We developed and tested a more comprehensive survey with over 1,600 diverse patients (African American, Spanish- and English-speaking Latinos, and whites), resulting in a revised conceptual framework and the Interpersonal Processes of Care (IPC) Survey. 

• Citation: Stewart AL, Nápoles-Springer AL, Gregorich SE and Santoyo-Olsson J.  Interpersonal processes of care survey: Patient-reported measures for diverse groups.  Health Services Research, 2007; 42 (3, Part I):1235-56.  PMCID: PMC1955252

Interpersonal Processes of Care: The Concept

We conceptualize interpersonal processes of care as multidimensional, comprising three domains, each with subdomains: communication (eliciting concerns, explanations), decision-making (shared decision-making), and interpersonal style (compassion, respectfulness).  Below is a link to a table that summarizes and compares the original (Stewart et al. 1999) and the revised (Stewart et al., 2007) frameworks, enabling visualization of the changes.  The original framework is the most comprehensive, and we recommend its use as a basis for continued development of concepts and measures of interpersonal processes of care for disparities research. 

What is the Interpersonal Processes of Care (IPC) Survey?

Although some investigators continue to use our 41-item Phase One (1999) survey instrument, we strongly recommend using our Phase Two (2007) instrument, which we named the Interpersonal Processes of Care (IPC) Survey.  The remainder of this document focuses exclusively on our Phase two (2007) survey instrument, which has 29 items, including an 18-item short scale.

In phase two (2007), we developed the Interpersonal Processes of Care (IPC) Survey, a patient-reported, multi-dimensional instrument assessing several aspects of communication, patient-centered decision-making, and interpersonal style.  We designed it to be appropriate for patients from diverse racial/ethnic groups. English- and Spanish-language versions are available.  Psychometric validation of the final IPC Survey was demonstrated with data from a sample of over 1,600 African American, Spanish- and English-speaking Latino, and white patients.  We aimed for a final set of measures that met measurement invariance criteria the four sampled groups.  The final survey includes 29 items (IPC-29).  The IPC-18 is a subset of 18 of the 29 items. 

• Citation: Stewart AL, Nápoles-Springer AL, Gregorich SE and Santoyo-Olsson J.  Interpersonal processes of care survey: Patient-reported measures for diverse groups.  Health Services Research, 2007; 42 (3, Part I):1235-56.  PMCID: PMC1955252

What is the difference between the Phase Two (2007) IPC-29 and IPC-18?  

The 29- and 18-item instruments demonstrated differing levels of measurement invariance across the four sampled racial/ethnic and language groups. The IPC-29 comprises twelve 1st-order and seven 2nd-order factors.  The seven 2nd-order factors demonstrated equivalent meaning (metric invariance) across the four population groups.  Derived scores for the IPC-29 are based on the 2nd-order factors (see scoring below). 

The IPC 18 short form includes items from one 1st-order factor per 2nd-order factor. These items demonstrated scalar invariance; in addition to providing evidence of equivalent meaning across groups, scalar invariance suggest that scale scores allow for unbiased mean comparisons across the four sampled population groups.

Investigators can choose between administering all 29 items (IPC-29) or the 18 item short form (IPC-18).  The 29-item and 18-item surveys performed well within each racial/ethnic/language group represented in the study sample. The 18-item short form can be used to make unbiased mean comparisons across these four groups.  Additionally, either form can be used for within-group studies.  Both the IPC-29 and the IPC-18 can be used to describe disparities in interpersonal processes of care, predict patient outcomes, and examine outcomes of quality improvement efforts to reduce health care disparities.

Copyright and Permission

Although the IPC is copyrighted, it is available without charge and no written permission is required for use. It is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC-BY-NC-SA).  

Use of our Phase Two (2007) 29- or 18-item IPC instrument implies agreement with the following terms and conditions.

Download IPC Surveys and Scoring Instructions

The IPC surveys are designed to be interviewer-administered (by telephone or in person) but can be self-administered. 

Evidence for the Validity of the IPC Survey.

The well-fitting 2nd-order factor model demonstrated conceptually coherent factors—providing evidence of construct validity—as well as key features of measurement invariance across four racial/ethnic/language groups (Stewart et al., 2007).  Additional evidence was provided by examination of associations of IPC-18 scales with measures of patient satisfaction, including whether associations varied by race, ethnicity, and language. 

• Citation: Nápoles AM, Gregorich SE, Santoyo-Olsson J, O’Brien H, and Stewart AL.  Interpersonal processes of care and patient satisfaction: do associations differ by race, ethnicity, and language? Health Services Research, 2009;44(4):1326-44. PMCID: PMC2714869

Funding

Development of the Phase Two (2007) IPC measure was supported by grant R01 HS10599 from the Agency for Healthcare Research and Quality.  It also was supported through a Resource Center on Minority Aging Research grant (P30 AG15272) from the National Institute on Aging, the National Institutes of Nursing research and the National Center on Minority Heath and Health Disparities, National Institutes of Health.  Phase One was sponsored by the Medical Effectiveness Research Center (MERC), a MEDTEP Center funded by a grant from the Agency for Health Care Policy and Research (HS07373).