Table 1.
Post- inverse probability of treatment weighting (IPTW) Baseline Demographic Characteristics.
| Characteristic | QIVc (N = 669,030) |
QIVe-SD (N = 3,062,797) | SMD 1 |
|---|---|---|---|
| Mean Age (years) | 36.8 | 36.9 | 0.01 |
| SD | 19.2 | 19.2 | |
| Median | 39 | 40 | |
| Age group (%) | |||
| 4–8 years | 10.0% | 9.6% | −0.01 |
| 9–17 years | 15.3% | 14.9% | −0.01 |
| 18–49 years | 40.1% | 40.5% | 0.01 |
| 50–64 years | 34.6% | 35.0% | 0.01 |
| Female (%) | 55.5% | 55.3% | 0.00 |
| Payer type (%) | |||
| Commercial | 60.8% | 60.4% | −0.01 |
| Medicaid | 0.7% | 0.8% | 0.00 |
| Medicare Advantage | 0.0% | 0.0% | 0.00 |
| Self-Insured | 38.4% | 38.8% | 0.01 |
| Unknown | 0.0% | 0.0% | 0.00 |
| Health plan type (n, %) | |||
| Consumer directed health care | 0.1% | 0.1% | 0.02 |
| HMO | 7.7% | 8.4% | 0.02 |
| POS | 5.4% | 6.2% | 0.03 |
| PPO | 85.9% | 84.3% | −0.05 |
| Other/Unknown | 0.9% | 1.0% | 0.02 |
| Geographic region (n, %) | |||
| Northeast | 15.1% | 16.6% | 0.04 |
| Midwest | 35.1% | 33.3% | −0.04 |
| South | 39.0% | 38.8% | 0.00 |
| West | 10.8% | 11.3% | 0.02 |
| DHHS (U.S. Dept. of Health and Human Services) region (%) | |||
| Region 1: CT, ME, MA, NH, RI, VT | 6.1% | 6.6% | 0.02 |
| Region 2: NJ, NY, PR, VI | 2.7% | 2.9% | 0.02 |
| Region 3: DE, DC, MD, PA, VA, WV | 8.7% | 9.0% | 0.01 |
| Region 4: AL, FL, GA, KY, MS, NC, SC, TN | 23.5% | 24.0% | 0.01 |
| Region 5: IL, IN, MI, MN, OH, WI | 26.1% | 24.5% | −0.04 |
| Region 6: AR, LA, NM, OK, TX | 13.4% | 13.2% | 0.00 |
| Region 7: IA, KS, MO, NE | 7.6% | 7.6% | 0.00 |
| Region 8: CO, MT, ND, SD, UT, WY | 3.0% | 2.8% | −0.01 |
| Region 9: AZ, CA, HI, NV, AS, FS, GU, PU | 3.0% | 3.2% | 0.01 |
| Region 10: AK, ID, OR, WA | 6.0% | 6.1% | 0.01 |
SMD = standardized mean difference; 1 SMD (absolute) ≥ 0.10 shows significant difference; IPTW = inverse probability of treatment weighting; POS = point-of-service; HMO = health maintenance organization; PPO = preferred provider organization; QIVc = cell-based quadrivalent influenza vaccine; QIVe-SD = standard-dose egg-based quadrivalent influenza vaccine; SD = standard deviation.