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Background: Age is the strongest risk factor for most chronic diseases, yet individuals age biologically at different rates. Summarising patterns of biomarkers that contribute strongly to overall and body system-specific ageing into biological and body system (bodily) ages may aid health risk communication and disease prevention. A systematic review (undertaken within this thesis) found that biological ages indicated or predicted poorer health, but few studies conducted validation or followed good practice for estimating and reporting biological ages. Methods: Among 480,019 UK Biobank participants aged 40-70 followed up for 6-12 years via linked death registry and hospital records, analyses focused on 141,254 (29.4%) participants healthy at baseline. Sex-specific biological ages were estimated from biomarker principal components (characterised from 72 physical and biochemical biomarkers) via two main approaches: (1) the age-based Klemera Doubal method, which emphasised biomarkers strongly related to chronological age, and (2) a novel disease risk-based approach of aggregating 8 body system ages (artery, musculoskeletal, gut, cardiac, metabolic disease, inflammatory, neurological and lung ages, each estimated using Cox lasso models) using a multi-state model. The proportions of the overall biological and chronological age effects on mortality from chronic disease, age-related frailty and the 8 groups of diseases explained by bodily ages were assessed using likelihood-based measures. Results: In healthy participants, reduced lung function, reduced kidney function, slower reaction time, lower insulin-like-growth factor 1 and lower hand grip strength strongly featured in the age-based biological age, while higher general adiposity was a shared risk factor across body system ages and therefore featured strongest in the disease risk-based biological age (together with lower central adiposity in men and lower hand grip strength in women). Although key biomarkers of body system ages were generally different from each other and from biomarkers strongly related to chronological age, biomarker patterns of body system ages apart from neurological age were moderately correlated (p=0.15-0.69). Gut, cardiac and neurological ages for men, and musculoskeletal and neurological ages for women contributed substantially to the prediction of mortality and frailty in the disease risk-based biological age. The age-based biological age overlapped with chronological age to explain two-thirds of the overall biological and chronological age effects on mortality and frailty. Biomarker constituents of the disease risk-based vs age-based biological ages alone explained 11-17% vs 2-8% of the overall effects on mortality and frailty, and the largest improvement was for frailty in healthy women. These proportions were higher when the analysis was repeated in the whole UK Biobank population (25-38% vs 15-35% for disease risk-based vs age-based biological ages). Biomarker constituents of body system ages explained 24-81% of the overall effects for their respective diseases in healthy participants. Conclusions: Bodily ages, particularly the novel disease risk-based ages, improved our understanding of the biomarker-disease relationships represented by chronological age and improved prognosis of later life health outcomes. Biomarkers across a range of body systems described a common ageing effect and substantial proportions of age effects on later life health, supporting a broader, multi-system risk-based approach to research and prevention of diseases of ageing.

Existing studies suggest that music performance anxiety can undermine the quality of performances regardless of performers’ ages. However, most of the studies have focused on professional musicians. It is crucial to know when music performance anxiety occurs in order to minimize its effects on young musicians including the ongoing psychological damage done to them. The present study is intended to investigate: 1) whether there was support for the claim that music performance anxiety has an early onset in young children; 2) to what extent music performance anxiety is associated with self-esteem; 3) whether there is support for the claim that performance outcomes are affected by one’s anxiety levels. The State-Trait Anxiety Inventory for Children (STAIC) by Spielberger (1973)and the Self-Esteem Scale (SES) by Rosenburg (1965) were the major psychometric measures. A researcher-designed questionnaire was also used to collect participants’ demographic data and their experiences as well as the ways they coped with music performance anxiety. They were asked to identify their feelings based on the items adapted from the Music Performance Anxiety Inventory for Adolescents or MPAI-A (Osborne and Kenny, 2005). One hundred and seventy-four participants aged from 7 to 18 participated in the present study. Findings of the present study suggest that age is significantly related to participants’ pre-SAS and the number of symptoms. In addition, MPA was found to be more prevalent in older age ranges but no significant differences were found between different age groups. In addition, evidence from the current study supported the claim that self-esteem is negatively correlated with MPA. It was also revealed that no relation was found between one’s music performance anxiety and the quality of music one played. However, participants’ anticipated outcomes of their quality of performance may be related to music performance anxiety. Findings from the study are discussed in terms of their relevance to the Hong Kong context and their implications for practice.

Recent educational reforms in Hong Kong aimed to increase choice, diversity and quality of education for everyone. The advocates of school-choice policies claim that more choice is good because it is ‘classless’ and fairer than planned provision (Chubb & Moe, 1990). Everyone has the chance to choose and to decide upon the best providers of goods and services to meet their needs. However, opponents (Gewirtz, Ball & Bowe, 1995) argue that social and cultural capitals may play an important role in choice-making. They conclude that choice is very directly and powerfully related to social class and that ‘choice emerges as a major new factor in maintaining and indeed reinforcing social-class divisions and inequalities’ (ibid: 55). All such literature prompts the question: what are the main effects of the new school choice policy implemented in Hong Kong in 2001? The focus of this research is, therefore, to investigate the early impact of the new school choice policy in Hong Kong and the reactions of parents and schools. In this thesis, I have employed a multi-method research strategy which includes case studies of fours schools, a questionnaire survey of 905 parents and interviews with parents, school managers and policy-makers in order to investigate the early impact of the new secondary school choice (SSPA) policy in Hong Kong. I examined how parents engaged in choosing schools and the subsequent consequences of the policy for the key stakeholders – consumers and providers. The richness of the data reveals the equality issues inherent in the choice process in the unique choice situation in Hong Kong.