A survey to assess the preference and self-efficacy of diet and physical activity choices

From the Greenlee Group, Public Health Sciences Division and Cancer Epidemiology, Prevention and Control Program of the Cancer Consortium

As we say in Spanish, “conocimiento es poder” or “knowledge is power”. This is the case for healthy behaviors which are linked to lower risk of cancer recurrence and improved survival. A growing number of lifestyle interventions are being developed to promote healthy lifestyles among breast cancer survivors; yet, Latina breast cancer survivors have limited guidance on these recommendations. So, how can Latina breast cancer survivors acquire the knowledge and skills necessary to change and maintain their dietary and physical activity habits? This is one of the major focuses for Dr. Heather Greenlee, an associate professor in the Public Health Sciences Division, and her research team. “Much of my group’s work focuses on developing and implementing programs to support Latinas with breast cancer in making changes to their diet and physical activity patterns” said Dr. Greenlee. To do so, Dr. Greenlee’s team has developed the Mi Vida Saludable (My Healthy Life) program which aims to promote healthy lifestyles among Latina Breast Cancer survivors who are at higher risk of obesity and generally have low physical activity rates and poor access to quality healthcare.

The Mi Vida Saludable program sought to change behaviors in Latina breast cancer survivors with four specific goals: 1.) increase physical activity, 2.) increase fruit and vegetable intake, 3.) decrease overall dietary fat intake, and 4.) decrease added sugar intake. But here is the catch: there is no agreed-upon scale to measure the effectiveness of these interventions. “Assessing behavioral lifestyle changes in diet and physical activity is tricky [because] there are few instruments which have been tested and validated in non-White populations” said Dr. Greenlee. “When we started the Mi Vida Saludable study we did not have a validated instrument to assess preferences and self-efficacy in four lifestyle habits: physical activity, fruit and vegetable intake, dietary fat intake, and added sugar intake.” Thus, Dr. Greenlee and her team “developed, tested, and validated a new scale.” They named this scale the Preference and Self-Efficacy of Diet and Physical Activity Behaviors Questionaries for Latina Women (PSEDPALW). This work was started when Dr. Greenlee was at Columbia University in New York. It was led by colleagues at Teachers College who have expertise in developing and testing health education curricula. The results of the development, validity, and reliability of PSEDPALW were recently published in Nutrients.  

The PSEDPALW questionnaire measures the preference and self-efficacy of the four behavior change goals mentioned above on a total of eight scales, for use in the Mi Vida Saludable program. Importantly, the questionnaire was developed in English and translated into Spanish. The questions for each scale were adapted from the Exercise and Nutrition Routine Improving Cancer Health (ENRICH) and the National Cancer Institute (NCI) Food Attitudes and Behaviors (FAB) programs. Participants in the study were from the Columbia University Medical Center and breast cancer patient database. Participants were at least 21 years old, identify as Latina/Hispanic, speak English or Spanish, have medical history of stage 0-III breast cancer with no evidence of metastatic disease, and are more than 90 days post-final treatment. Participants also had to consume less than 5 pieces of fruit and vegetables per day and/or practice moderate exercise. In all, five cohorts of Latina breast cancer survivors participated in the study.

Mi Vida Saludable (My Healthy Life) is a diet and physical activity educational program specifically geared towards Latina breast cancer survivors
Mi Vida Saludable (My Healthy Life) is a diet and physical activity educational program specifically geared towards Latina breast cancer survivors Image taken from the Greenlee Lab website

First, the authors evaluated the content and face validity of the questionnaire. Face validity measures whether a question or survey actually measures what it is intended to measure.  In this case, it determined whether participants had difficulty understanding the questionnaire and formulating their answers. To accomplish this, participants (who met the previous criteria) were recruited for cognitive interviews. Participants completed both the questionnaire and a group discussion. An expert review panel assessed the clarity, cultural appropriateness, and understandability of the questions (content validity). 

The authors then assessed reliability based on internal consistency and test-retest. Internal consistency determined if the scales for preferences and self-efficacy for each of the four behavior change goals are homogenous. These was done with the questionnaires completed by the participants in the Mi Vida Saludable program. Internal consistency of each scale was measured by calculating Cronbach's Alpha (statistic analysis that measures internal consistency of a set of survey items). The test-retest is a method of evaluating the reliability of a test that is administered twice. For this, participants could complete the questionnaire twice, one to three weeks after the first one.

Overall, the authors found that the internal consistency and reliability of the eight scales were good to moderate and similar to the ones they derived, the FAB and ENRICH. “We found that parts of the questionnaire performs better than others” Dr. Greenlee commented. “We will continue to refine this.” Excitingly, Dr. Greenlee and her team will be able to continue their work with a “newly funded R01 testing a diet and physical activity weight loss program for Latina breast cancer survivors.” 

The spotlighted research was supported by grants from the National Cancer Institute and the National Center for Advancing Translational Science. 

Fred Hutch/University of Washington/Seattle Children's Cancer Consortium members Drs. Salene Jones and Heather Greenlee contributed to this work.

Koch PA, Paul R, Contento IR, Gray HL, Marín-Chollom AM, Santiago-Torres M, Shen H, Jones SMW, Hershman DL, Greenlee H. 2023. Mi Vida Saludable: Content Validity and Reliability of The Preferences and Self-Efficacy of Diet and Physical Activity Behaviors Questionnaire for Latina Women (PSEDPALW) for Cancer Survivors. Nutrients. 12;15(16):3563. doi: 10.3390/nu15163563