Table 1.
Construction of the 3Cs concepts from survey responses
| Indicator | Description | Questionnaire items * | Construction | Measurement scale (and points) |
|---|---|---|---|---|
| Confidence in the vaccine | Level of perception of the efficacy and safety of the vaccine | 24.1: “Vaccine efficacy level”. 24.2: “Vaccine safety level”. 25.1: “The vaccine is very effective” |
Points added gradually according to ordinal answers obtained in questions. Resulting sum is rescaled to the interval (0,1) and expressed as %. | From low confidence (0 Pnts.) to high confidence (12 Pnts.). The more confidence, the less hesitation to vaccinate |
| Complacency A. Influenza risk | Level of perception of the risk of contracting influenza and its severity | 24.3: “Level of risk of contracting influenza.” 24.4: “Flu severity level”. |
Idem. | From low risk (0 Pnts.) to high risk (8 Pnts.) The greater the risk, the less hesitation to be vaccinated |
| Complacency B. Knowledge of influenza and the vaccine | Level of knowledge of influenza and its vaccine | 11: “You know what influenza is.” 12: “Main symptoms of influenza.” 13: “You know the vaccine exists” 25.5: “It is advisable to vaccinate against influenza every year.” 25.6: “Only minors and the elderly should be vaccinated.” (Calculated in an inverted sense to be consistent with the direction of the indicator) |
Points added for positive answers in each of the questions. Resulting sum is rescaled to the interval (0,1) and expressed as %. | From low knowledge (0 Pnts.) to high knowledge (25 Pnts.) The more knowledge, the less hesitation to vaccinate |
| Complacency C. Vaccine prejudices | Level of prejudices expressed about influenza vaccine | 25.2: “The vaccine has side effects.” 25.4: “The vaccine causes reactions.” |
Points added gradually according to ordinal answers obtained in questions. Resulting sum is rescaled to the interval (0,1) and expressed as %. (The percentage complement is used to be consistent with the direction of the indicator) | From low prejudice (0 Pnts.) to high prejudice (8 Pnts.) A lower value, less prejudice and less hesitation to get vaccinated |
| Convenience | Level of convenience perceived in accessing the vaccine | 19. Who recommended you get vaccinated? 20. Do you know where to go to get a flu shot? 22. Is the vaccine available at the health facility where you go regularly? 23. How long does it take to get from your home to the health facility you go to regularly? 25.3 Is the flu vaccine difficult to obtain? |
Categorization and point addition in each question. Sum is rescaled to the interval (0,1) and is expressed as %. | From low convenience (0 Pnts.) to high convenience (5 Pnts.) The more convenience, the less hesitation to vaccinate |
* Reference is made to the questionnaire for Adults with Risk factors. Questionnaires for other risk groups specified question 25.6. Questionnaire is available as supplementary material.