A trial was carried out in three general practices in the Canada to find out whether telephoning patients to offer them an appointment for immunization against COVID-19 would increase immunization uptake. In this study, attending the appointment for an immunization was the outcome of interest and receiving a telephone call was the exposure. A total of 1318 patients aged 65 to 74 years were randomly assigned to two groups. Patients in one group (n = 660) received a telephone call regarding an immunization appointment. Patients in the other group (n = 658) were not called. Of the patients who received a phone call, 328 attended the appointment for immunization as did 288 of those not called.
How many times more likely were patients to attend if they had received a personal call to make an appointment than if they had not been telephoned? (calculate to one decimal point)