People Selected for Entred-Métropole

The Health Insurance Agency conducted a random drawing among individuals:

• aged 18 or older;

• residing in mainland France;

• insured by or beneficiaries of the National Health Insurance Fund for Salaried Workers (CnamTS) or the Social Security Scheme for the Self-Employed (RSI);

• who have received at least three reimbursements for oral antidiabetic medications and/or insulin over the past 12 months

The random selection was based on registration codes (the last two digits of the Social Security number). For the CnamTS, 44% of adults with diabetes from a given registration key were randomly selected; for merchants and artisans in the RSI, 53% from a given key; and for self-employed professionals in the RSI, all adults with diabetes from three registration keys. This was done to obtain a sample of approximately 8,000 people affiliated with the CnamTS, 300 merchants, 300 artisans, and 300 self-employed professionals with diabetes, and to specifically compare these last three groups.

In total, 8,926 adults with diabetes residing in mainland France were included, of whom 7,989 were affiliated with the CnamTS, 317 were merchants, 298 were artisans, and 322 were self-employed professionals.

Conduct of the Entred-Métropole Study

Data collection for the Entred-Métropole study took place in four main stages:

A “medical advisor” survey, conducted from October to December 2007

At each participating local health insurance fund, a medical advisor sent a letter [pdf - 208 KB] to the selected individuals with diabetes to:

• explain the purpose of the 2007 Entred study;

• invite them to participate in the study;

• ask for their phone number and the times they prefer to be contacted.

After receiving the person’s consent and contact information, the medical advisor calls the person to briefly review the survey procedures and conducts a short telephone interview lasting approximately 7 minutes.

A “patient” survey, from October 2007 to January 2008

The medical advisor then sends a letter to all individuals who did not decline to participate in the study. This letter includes:

• a new information letter;

• a detailed questionnaire;

• a request for the contact information of the doctor(s) treating the person for their diabetes (primary care physician or specialist).

Respondents return their questionnaire and the contact information for their treating physicians directly to the French Institute for Public Health Surveillance (InVS) in a confidential T-envelope.

A “physician” survey, from November 2007 to June 2008

For people with diabetes who have returned both their self-administered questionnaire and provided the contact information for their treating physician(s) (general practitioners or specialists), InVS survey doctors contact the treating physicians (specialists first) by phone to introduce them to the Entred study and send them an informational letter by mail along with a medical questionnaire regarding their patient (interview lasting approximately 10–15 minutes). This medical questionnaire concerns their patient as well as their usual practices for managing people with diabetes.

A “healthcare utilization” survey

In parallel with these three steps, data on reimbursements for medications, medical procedures (consultations, laboratory tests), medical supplies, and hospitalizations for the 8,926 people with diabetes were gradually extracted from the Health Insurance databases, as well as from the Medical Information Systems Program (PMSI), which records all stays in healthcare facilities, for those who did not refuse to participate in the study. This data is transmitted anonymously to the InVS for analysis over three consecutive years.

Entred-Métropole Questionnaires

Questionnaire administered by telephone by medical advisors

“Patient” questionnaire mailed to people with diabetes

“Physician” questionnaire mailed to the physicians of people with diabetes