Table 2.

Expert Opinions About the Three Bias Parameters and the Assigned Distributions

Bias Parameters	95% Prior Interval (by Expert Opinion)		Prior Distributions
	Expert 1	Expert 2	Expert 1	Expert 2
a) Proportion of young adult PWID with insufficient HIV knowledge among unsafe injectors	2.5%–9.5%	20%–40%	Beta distribution (α = 8.65, β = 149.42)	Beta distribution (α = 23.11, β = 55.21)
b) Proportion of young adult PWID with insufficient HIV knowledge among low-risk injectors	1%–6%	10%–20%	Beta distribution (α = 5.12, β = 166.35)	Beta distribution (α = 27.83, β = 162.15)
c) Risk Ratio of the association between insufficient HIV knowledge and NBT for HIV among low-risk injectors	1.1–2.2	1.1–5	Normal distribution (μ = 0.44, σ = 0.18)	Normal distribution (μ = 0.85, σ = 0.39)