title: From perceived autonomy support to intentional behaviour: Testing an integrated model in three healthy-eating behaviours.
abstract: A motivational model integrating self-determination theory, the theory of planned behaviour, and the health action process approach was tested in three samples in three behavioural contexts: fruit and vegetable, breakfast, and snack consumption. Perceived support for autonomous (self-determined) forms of motivation from parents and autonomous motivation from self-determination theory were hypothesised to predict intention and behaviour indirectly via the mediation of attitude and perceived behavioural control from the theory of planned behaviour. It was also expected that planning strategies would mediate the effect of intention on behaviour. Relations in the proposed models were expected to be similar across the behaviours. A two-wave prospective design was adopted. Three samples of high-school students (total N = 1041; 59.60% female; M age = 17.13 years ± 1.57) completed measures of perceived autonomy support, autonomous motivation, theory of planned behaviour constructs, planning strategies and behaviour for each of the three behavioural contexts. Three months later, 816 participants (62,24% female; M age: 17.13 years, SD = 1.58) of the initial sample self-reported their behaviour referred to the previous three months. Structural equation models provided support for the key hypothesised effects of the proposed model for the three health-related behaviours. Two direct effects were significantly different across the three behaviours: the effect of perceived autonomy support on perceived behavioural control and the effect of attitude on intention. In addition, planning strategies mediated the effect of intention on behaviour in fruit and vegetable sample only. Findings extend knowledge of the processes by which psychological antecedents from the theories affect energy-balance related behaviours.
authors.affiliation: Department of Psychology of Development and Socialization Processes - Sapienza, University of Rome, Italy. Electronic address: laura.girelli@uniroma1.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Girelli
authors.affiliation: Health Psychology and Behavioural Medicine Research Group, School of Psychology and Speech Pathology, Curtin University, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Hagger
authors.affiliation: Department of Psychology of Development and Socialization Processes - Sapienza, University of Rome, Italy; Department of Movement, Human and Health Sciences, University of Rome, "Foro Italico", Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Mallia
authors.affiliation: Department of Psychology of Development and Socialization Processes - Sapienza, University of Rome, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Lucidi
mesh_terms: D000293:Adolescent; D005247:Feeding Behavior / Q000523:psychology*; D005260:Female; D005638:Fruit; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006293:Health Promotion; D006801:Humans; D033182:Intention; D008297:Male; D008960:Models, Psychological; D026684:Personal Autonomy; D011446:Prospective Studies; D011582:Psychological Theory; D057566:Self Report; D062410:Snacks; D013334:Students / Q000523:psychology; D011795:Surveys and Questionnaires; D014675:Vegetables
keywords: Breakfast; Fruit and vegetable; Planning; Self-determination theory; Snack consumption; Theoretical integration; Theory of planned behaviour