Let $P = (\Omega, \mathcal{F}, \mathbb{P})$ be D1159: Probability space such that

(i)	$\mathsf{Subnull} = \mathsf{Subnull}(P)$ is the D3804: Set of subnull sets in $P$

Then $\mathbb{P}$ is a complete probability measure if and only if \begin{equation} \mathsf{Subnull} \subseteq \mathcal{F} \end{equation}