Study	Reason for exclusion
Ajrouch 2010	No in‐work tax credit for families intervention was studied (or the study combined one or more in‐work tax credit for families interventions with other publicly funded financial credit interventions)
Alegria 2003	No empirical data were studied
Arno 2009	Participants were not working‐age adults
Baker 1999	No in‐work tax credit intervention was studied
Greenberg 2009	No in‐work tax credit intervention was studied
Gregg 2007	The combined effect of an in‐work tax credit and a set of other welfare‐to‐work interventions was studied
Hoynes 2011	Participants were not working‐age adults
Kenkel 2011	The in‐work tax credit intervention was used as an instrumental variable to estimate the impact of income on health, but the impact of the in‐work tax credit on health was not estimated
Kneipp 2000	No in‐work tax credit intervention was studied
Larrimore 2011	The in‐work tax credit intervention was used as an instrumental variable to estimate the impact of income on health, but the impact of the in‐work tax credit on health was not estimated
Martin 2012	No in‐work tax credit intervention was studied
Pollack 2006	No in‐work tax credit intervention was studied
Rehkopf 2011	Participants were not working‐age adults
Rodriguez 2001	No in‐work tax credit intervention was studied (or the study combined one or more in‐work tax credit interventions with other publicly funded financial credit interventions)
Rodriguez 2006	No in‐work tax credit intervention was studied (or the study combined one or more in‐work tax credit interventions with other publicly funded financial credit interventions)
Schmeiser 2009	The in‐work tax credit intervention was used as an instrumental variable to estimate the impact of income on health, but the impact of the in‐work tax credit on health was not estimated
Zabkiewicz 2010	No in‐work tax credit intervention was studied