Assessing SB as a sum of behaviours and using a previous day recall were the most promising features of existing tools .
Accuracy was poor for all existing tools , with underestimation and overestimation of SB .
There was a lack of evidence about sensitivity to change .
OBJECTIVE Sedentary behaviour ( SB ) has distinct deleterious health outcomes , yet there is no consensus on best practice for measurement .
This study aim ed to identify the optimal self-report tool for population surveillance of SB , using a systematic framework .
Reliability and Validity of a Domain-Specific Last 7-d Sedentary Time Questionnaire
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Assessing SB as a sum of behaviours and using a previous day recall were the most promising features of existing tools .
Accuracy was poor for all existing tools , with underestimation and overestimation of SB .
There was a lack of evidence about sensitivity to change .
OBJECTIVE Sedentary behaviour ( SB ) has distinct deleterious health outcomes , yet there is no consensus on best practice for measurement .
This study aim ed to identify the optimal self-report tool for population surveillance of SB , using a systematic framework .