Table 1.
Epidemiological input values and sources applied in base case, sensitivity and scenario analyses
| Years of age | Base value | Lower bound for DSA | Upper bound for DSA | SE for PSA |
|---|---|---|---|---|
| Population size used to determine the proportions in the 1 million cohort | ||||
| 50–59 | 15,749,000 | – | – | – |
| 60–64 | 7,805,000 | – | – | – |
| 65–69 | 9,921,000 | – | – | – |
| 70–79 | 14,486,000 | – | – | – |
| ≥ 80 | 10,744,000 | – | – | – |
| Source | (24) | NA | NA | – |
| Annual incidence of initial and recurrent HZ | ||||
| 50–59 | 0.00920 | – | – | – |
| 60–69 | 0.00960 | 0.00768 | 0.01152 | 0.000980 |
| 70–79 | 0.01290 | 0.01032 | 0.01548 | 0.001320 |
| ≥ 80 | 0.01260 | 0.01008 | 0.01512 | 0.001290 |
| Source | (7)a | − 20%: (26, 27)a | + 20%: assumptiona | |
| Initial and recurrent HZ cases with PHN (%) | ||||
| 50–59 | 14.60 | – | – | – |
| 60–69 | 14.60 | 7.30 | 17.52 | 0.0261 |
| 70–79 | 20.20 | 10.10 | 24.24 | 0.0361 |
| ≥ 80 | 32.90 | 16.45 | 39.48 | 0.0588 |
| Source | (7)b | − 50%: (25)b | + 20%: assumptionb | |
| HZ-related complications other than PHN (%) | ||||
| 50–69 | 5.1 | 1.9 | 8.3 | 0.0165 |
| ≥ 70 | 10.6 | 6.7 | 14.5 | 0.0201 |
| Source | (11)c | (11)c | (11)c | |
| HZ mortality rate (%) | ||||
| 50–69 | 0.0000 | – | – | – |
| 70–74 | 0.0020 | – | – | – |
| 75–79 | 0.0092 | – | – | – |
| 80–84 | 0.0210 | – | – | – |
| 85–89 | 0.0467 | – | – | – |
| 90–94 | 0.1204 | – | – | – |
| 95–99 | 0.1960 | – | – | – |
| ≥ 100 | 0.9476 | – | – | – |
| Source | (7, 24) | NA | NA | – |
DSA deterministic sensitivity analysis, HZ herpes zoster, PHN postherpetic neuralgia, PSA probabilistic sensitivity analysis, RZV recombinant zoster vaccine, SE standard error
aTakao et al. reported an incidence rate of HZ in a community-based prospective cohort study [7]. The lower bound estimates were obtained from Toyama et al. [26, 27], and − 20% was set based on the adjusted values by the updated HZ incidence (4.15 in 1997–2006 vs. 6.07 in 2017); assumed + 20% of base case for the upper bound. The recurrent HZ incidence was assumed to be the same as the initial HZ incidence
bThe percentage of HZ with PHN was obtained from the same data source as the HZ incidence. The lower bound estimates were obtained from Sato et al. [25]; − 50% was set based on the ratio of total PHN proportion in the two studies (9.2%/19.7%); assumed + 20% of the base case for the upper bound. The PHN proportion among HZ was assumed to be the same for both initial and recurrent cases
cNakamura et al. reported overall incidence of non-pain complications including ocular, neurological and cutaneous ones in a prospective, observational cohort study of Japanese adults aged ≥ 60 [11]. The incidence at ages 50–59 was assumed to be the same as that at ages 60–69. Ranges were set as 95% confidence intervals calculated from the published data in Nakamura et al. [11]