Table 4 Domains, descriptions and study operational descriptions. 10 TDF domains and two new created domains captured by NHANES 2011–2012 items and four of the 14 TDF original domains not captured by NHANES items

Knowledge^a

Awareness of the existence of something

Awareness of the dietary guidelines, their general health and health risks factors and the benefits of sports and recreational activities

Beliefs about capabilities^a

Acceptance of the truth, reality, or validity about an ability, talent, or facility that a person can put to constructive use

An individual’s belief about self-confidence, control, or performance concerning making appropriate dietary choices, staying healthy and engaging in sports and recreational activities

Beliefs about consequences^a

Acceptance of the truth, reality, or validity about outcomes of a behavior in a given situation

An individual’s subjective rating of his/her general health, diet, and weight and his/her belief about the outcomes of making appropriate dietary choices, staying healthy and engaging in sports and recreational activities

Reinforcement^a

Increasing the probability of a response by arranging a dependent relationship, or contingency, between the response and a given stimulus

Internal or external responses to a person’s behavior that affect the likelihood of making appropriate dietary choices, staying healthy and engaging in sports, fitness and recreational activities

Memory, attention and decision processes^a

The ability to retain information, focus selectively on aspects of the environment, and choose between two or more alternatives

The ability to retain information concerning diet and health and to be able to focus on making appropriate dietary and health choices

Environ-mental context and resources^a

Any circumstance of a person’s situation or environment that discourages or encourages the development of skills and abilities, independence, social competence, and adaptive behavior

Any characteristics of the socio-political context, organization, and the person that discourages or encourages a person to make appropriate dietary choices, stay healthy and engage in sports and recreational activities

Social influences^a

Those interpersonal processes that can cause an individual to change their thoughts, feelings, or behaviors

An individual’s association with people and situations in society that dictates the way he/she thinks about things that might affect his/her diet, health, and sports and recreational activity level

Behavioral regulation^a

Anything aimed at managing or changing objectively observed or measured actions

All the things a person does concerning their diet, health and sports and recreational activities

Optimism^a

The confidence that things will happen for the best, or that desired goals will be attained

An individual’s confidence that things will happen for the best; never give up hope or look at the bright side of life

Emotion^a

A complex reaction pattern, involving experiential, behavioral, and physiological elements, by which the individual attempts to deal with a personally significant matter or event

A subjective psychophysiological experience that might affect a person’s likelihood of making appropriate dietary and health choices, and engaging in sports and recreational activities

Skills ^{a, b}

An ability or proficiency acquired through practice

The competence or capacity that help a person routinely manage otherwise his/her diet and health in a productive manner, making appropriate dietary choices, staying healthy, and engaging in sports and recreational activities

Social/professional role and identity^{a, b}

A coherent set of behaviors and displayed personal qualities of an individual in a social or work setting

A coherent set of dietary and health promotion behaviors and displayed personal qualities of an individual in a social setting

Intentions^{a, b}

A conscious decision to perform a behavior or a resolve to act in a certain way

Readiness/commitment to make healthy dietary choices, stay healthy and engage in sports and recreational activities

Goals^{a, b}

Mental representation of outcomes or end states that an individual wants to achieve

An aim or an objective a person wants to achieve concerning their diet and health

^cHealth Identity

New domain created; not part of TDF

A person sense of self/identity in view of a health characteristic that he/she may have to identify with or has identified with

^cFunctional Status

New domain created; not part of TDF

Any functional limitations caused by long-term physical, mental, and emotional problems or illness that impact an individual’s ability to make appropriate life choices and to engage in activities that promote a healthy lifestyle