Table 3. Colour coding definitions when responding to NPT questions using the evidence provided in publications.

Colour coding	Closed question	Open question
Green	Clear evidence in the publication that the question can be answered with a ‘yes’*.	Evidence in one or more publications that the impact of the implementation has been positive with respect to the question.
Amber	Partial evidence that the question can be answered with a ‘yes’* OR Evidence for both ‘yes’* and ‘no’ responses.	Partial evidence that the impact of the implementation was positive OR Evidence that there were positive and negative impacts of the implementation
Red	Clear evidence in the publications that the question can be answered with a ‘no’*.	Evidence in one or more publications that the impact of the implementation has been negative with respect to the question.
Grey	No evidence can be found to answer with either ‘yes’* or ‘no’.	No evidence in any of the publications of the impact with respect to the question.

^*Yes answers range from 6% to 69%, with a median value of 38%. ‘Not reported’ ranges from 0% to 69%, with a median value of 31%. Dugdale et al (X) and Jefferies et al (CC) scored the highest, with 69% positive responses.

NPT, normalisation process theory.