Environmental and Life-history Factors Influencing Juvenile Demography of a Temperate Reef Fish

Realistic population models and effective conservation strategies require a thorough understanding of the processes that drive variation in individual growth and survival, particularly within life stages that are subject to high mortality. For fragmented marine populations it is also important to consider how processes driving variation performance may vary through space and time. In this study I assess the interaction of two primary factors driving juvenile demography: benthic habitat composition and larval history traits, in a temperate reef fish, Forsterygion lapillum (the common triplefin). It is well understood that juveniles of many marine organisms are closely associated with structured nearshore habitats as they provide resources (refuge and food sources) that are critical for juvenile growth and/or survival. Nursery habitats are often assessed using measures of fitness of juveniles inhabiting them (e.g. rates of growth). However individual fitness measures may not only be indicative of conditions experienced in the benthic phase, but also an individual's prior history. Recent evidence suggests that variation in larval traits at settlement (e.g., size and age at settlement, larval growth rate) can impact on subsequent ecological performance (e.g., feeding ability and/or predator avoidance) and therefore influence subsequent fitness (i.e. rates of growth and/or probabilities of survival). I used otolith microstructure to assess separate and joint effects of habitat composition and larval traits on the growth of young F. lapillum. Both macroalgal composition of habitat patches and larval traits affected juvenile growth rates, and results suggested that habitat composition may have the potential to mediate fitness-related advantages that may accrue to certain individuals as a result of paternal effects and/or larval dispersal history. Quantifying spatio-temporal variability in the post-settlement fitness of Individuals with that differ in larval traits is essential for effective spatial management of marine populations. I further explore the joint effects of macroalgal composition and larval traits, within the context of additional spatial and temporal environmental variation. Results provide direct evidence that habitat can mediate the strength of carryover effects, but that the impact of habitat was variable between local populations and settlement events through time. In chapter 4 of my thesis, I focus on how small-scale variation in macroalgal composition within a nursery habitat (while controlling for individual variation) can affect the strength of density dependent growth and survival rates of F. lapillum. Density-dependent survival is evident during the first 30 days after settlement, and the strength of density dependence varied as a function of macroalgal composition. Resulting variation in estimates of nursery value (i.e., the number of late-stage juveniles produced per area unit of habitat) highlight the importance of incorporating local scale variation in juvenile demography into assessments of nursery habitat. Lastly, I assess a potential strategy of fishes to persist in a wide range of benthic environments. The ability to adjust traits (i.e., phenotypic plasticity) may allow organisms that encounter a range of unpredictable environmental conditions to maximise fitness within a single generation. In chapter 5 I explore patterns of variation in morphology of juvenile F. lapillum from two different subpopulations and from different macroalgal habitats. I evaluate possible evidence for constraints on morphological variation arising from variation in growth rate prior to and following settlement. Results suggest that for organisms with complex life cycles, variation in growth rates experienced during dispersal may constrain plasticity in later stages

Acute stress disorder and the transition to posttraumatic stress disorder in children and adolescents: Prevalence, course, prognosis, diagnostic suitability, and risk markers.

BACKGROUND: Early recovery from trauma exposure in youth is poorly understood. This prospective longitudinal study examined the early course of traumatic stress responses in recently trauma-exposed youth, evaluated the revised DSM-5 acute stress disorder (ASD) and PTSD diagnoses and alternative diagnoses, and identified risk factors for persistent traumatic stress. METHOD: Participants were 8- to 17-year-old emergency departments attendees exposed to single incident traumas. Structured clinical interviews were undertaken at 2 (n = 226) and 9 weeks (n = 208) posttrauma. RESULTS: Using the revised criteria in DSM-5, 14.2% met criteria for ASD at week 2 and 9.6% met criteria for PTSD at week 9. These prevalences were similar to the corresponding DSM-IV diagnoses (18.6% ASD at week 2; 8.7% PTSD at week 9). Using the same diagnostic criteria (DSM-IV or DSM-5) across assessments (i.e., "2-week PTSD") suggested that caseness declined in prevalence by approximately half. Overlap between DSM-IV and DSM-5 ASD and DSM-5 preschool child PTSD diagnoses was considerable. Two diagnoses were strongly predictive of corresponding week 9 diagnoses. Youth with ASD who subsequently had PTSD reported more negative alterations in cognition and mood at 2 weeks than those youth who did not develop PTSD. CONCLUSIONS: Youth exposed to single-event traumas experience considerable natural recovery in the first months posttrauma. Using DSM-5 criteria, ASD may not capture all clinically significant traumatic stress in the acute phase and is only moderately sensitive for later PTSD. Future research needs to address the role and etiology of negative alterations in cognition and mood symptoms

A core role for cognitive processes in the acute onset and maintenance of post-traumatic stress in children and adolescents.

BACKGROUND: Post-traumatic stress disorder (PTSD) is a common reaction to trauma in children and adolescents. While a significant minority of trauma-exposed youth go on to have persistent PTSD, many youths who initially have a severe traumatic stress response undergo natural recovery. The present study investigated the role of cognitive processes in shaping the early reactions of child and adolescents to traumatic stressors, and the transition to persistent clinically significant post-traumatic stress symptoms (PTSS). METHODS: A prospective longitudinal study of youth aged 8-17 years who had attended a hospital emergency department following single trauma was undertaken, with assessments performed at 2-4 weeks (N = 226) and 2 months (N = 208) post-trauma. Acute stress disorder and PTSD were assessed using a structured interview, while PTSS, depression severity and peritraumatic and post-traumatic cognitive processes were assessed using self-report questionnaires. On the basis of their PTSS scores at each assessment, participants were categorised as being on a resilient, recovery or persistent trajectory. RESULTS: PTSS decreased between the two assessments. Cognitive processes at the 2- to 4-week assessment accounted for the most variance in PTSS at both the initial and follow-up assessment. The onset of post-traumatic stress was associated particularly with peritraumatic subjective threat, data-driven processing and pain. Its maintenance was associated with greater peritraumatic dissociation and panic, and post-traumatic persistent dissociation, trauma memory quality, rumination and negative appraisals. Efforts to deliberately process the trauma were more common in youth who experienced the onset of clinically significant PTSS. Regression modelling indicated that the predictive effect of baseline negative appraisals remained when also accounting for baseline PTSS and depression. CONCLUSIONS: Cognitive processes play an important role in the onset and maintenance of PTSS in children and adolescents exposed to trauma. Trauma-related appraisals play a particular role when considering whether youth make the transition from clinically significant acute PTSS to persistent PTSS

The Preliminary Development and Validation of a Trauma‐Related Safety‐Seeking Behavior Measure for Youth: The Child Safety Behavior Scale (CSBS)

Safety‐seeking behaviors (SSBs) may be employed after exposure to a traumatic event in an effort to prevent a feared outcome. Cognitive models of posttraumatic stress disorder propose SSBs contribute to maintaining this disorder by preventing disconfirmation of maladaptive beliefs and preserving a sense of current threat. Recent research has found that SSBs impact children's posttraumatic stress symptoms (PTSS) and recovery. In this paper, we sought to develop and validate a novel 22‐item Child Safety Behavior Scale (CSBS) in a school‐based sample of 391 pupils (age 12–15 years) who completed a battery of questionnaires as well as 68 youths (age 8–17 years) who were recently exposed to a trauma. Of the sample, 93.1% (N = 426) completed the new questionnaire. The sample was split (n = 213), and we utilized principal components analysis alongside parallel analysis, which revealed that 13 items loaded well onto a two‐factor structure. This structure was superior to a one‐factor model and overall demonstrated a moderately good model of fit across indices, based upon a confirmatory factory analysis with the other half of the sample. The CSBS showed excellent internal consistency, r = .90; good test–retest reliability, r = .64; and good discriminant validity and specificity. In a multiple linear regression, SSBs, negative appraisals, and number of trauma types each accounted for unique variance in a model of PTSS. This study provides initial support for the use of the CSBS in trauma‐exposed youth as a valuable tool for further research, clinical assessment, and targeted intervention

The latent structure of Acute Stress Disorder symptoms in trauma-exposed children and adolescents.

BACKGROUND: The revision of Acute Stress Disorder (ASD) in the DSM-5 (DSM-5, 2013) proposes a cluster-free model of ASD symptoms in both adults and youth. Published evaluations of competing models of ASD clustering in youth have rarely been examined. METHODS: We used Confirmatory Factor Analysis (combined with multigroup invariance tests) to explore the latent structure of ASD symptoms in a trauma-exposed sample of children and young people (N = 594). The DSM-5 structure was compared with the previous DSM-IV conceptualization (4-factor), and two alternative models proposed in the literature (3-factor; 5-factor). Model fit was examined using goodness-of-fit indices. We also established DSM-5 ASD prevalence rates relative to DSM-IV ASD, and the ability of these models to classify children impaired by their symptoms. RESULTS: Based on both the Bayesian Information Criterion, the interfactor correlations and invariance testing, the 3-factor model best accounted for the profile of ASD symptoms. DSM-5 ASD led to slightly higher prevalence rates than DSM-IV ASD and performed similarly to DSM-IV with respect to categorising children impaired by their symptoms. Modifying the DSM-5 ASD algorithm to a 3+ or 4+ symptom requirement was the strongest predictor of impairment. CONCLUSIONS: These findings suggest that a uni-factorial general-distress model is not the optimal model of capturing the latent structure of ASD symptom profiles in youth and that modifying the current DSM-5 9+ symptom algorithm could potentially lead to a more developmentally sensitive conceptualization

Cognitive therapy as an early treatment for post-traumatic stress disorder in children and adolescents: a randomized controlled trial addressing preliminary efficacy and mechanisms of action.

BACKGROUND: Few efficacious early treatments for post-traumatic stress disorder (PTSD) in children and adolescents exist. Previous trials have intervened within the first month post-trauma and focused on secondary prevention of later post-traumatic stress; however, considerable natural recovery may still occur up to 6-months post-trauma. No trials have addressed the early treatment of established PTSD (i.e. 2- to 6-months post-trauma). METHODS: Twenty-nine youth (8-17 years) with PTSD (according to age-appropriate DSM-IV or ICD-10 diagnostic criteria) after a single-event trauma in the previous 2-6 months were randomly allocated to Cognitive Therapy for PTSD (CT-PTSD; n = 14) or waiting list (WL; n = 15) for 10 weeks. RESULTS: Significantly more participants were free of PTSD after CT-PTSD (71%) than WL (27%) at posttreatment (intent-to-treat, 95% CI for difference .04-.71). CT-PTSD yielded greater improvement on child-report questionnaire measures of PTSD, depression and anxiety; clinician-rated functioning; and parent-reported outcomes. Recovery after CT-PTSD was maintained at 6- and 12-month posttreatment. Beneficial effects of CT-PTSD were mediated through changes in appraisals and safety-seeking behaviours, as predicted by cognitive models of PTSD. CT-PTSD was considered acceptable on the basis of low dropout and high treatment credibility and therapist alliance ratings. CONCLUSIONS: This trial provides preliminary support for the efficacy and acceptability of CT-PTSD as an early treatment for PTSD in youth. Moreover, the trial did not support the extension of 'watchful waiting' into the 2- to 6-month post-trauma window, as significant improvements in the WL arm (particularly in terms of functioning and depression) were not observed. Replication in larger samples is needed, but attention to recruitment issues will be required

Developing a model of short-term integrated palliative and supportive care for frail older people in community settings: perspectives of older people, carers and other key stakeholders

Background: Understanding how best to provide palliative care for frail older people with non-malignant conditions is an international priority. We aimed to develop a community-based episodic model of short-term integrated palliative and supportive care (SIPS) based on the views of service users and other key stakeholders in the United Kingdom. Method: Transparent expert consultations with health professionals, voluntary sector and carer representatives including a consensus survey; and focus groups with older people and carers were used to generate recommendations for the SIPS model. Discussions focused on three key components of the model: potential benefit of SIPS; timing of delivery; and processes of integrated working between specialist palliative care and generalist practitioners. Content and descriptive analysis was employed and findings integrated across the data sources. Findings: We conducted two expert consultations (n=63), a consensus survey (n=42) and three focus groups (n=17). Potential benefits of SIPS included holistic assessment, opportunity for end of life discussion, symptom management, and carer reassurance. Older people and carers advocated early access to SIPS, while other stakeholders proposed delivery based on complex symptom burden. A priority for integrated working was the assignment of a key worker to coordinate care, but the assignment criteria remain uncertain. Interpretation: Key stakeholders agree that a model of SIPS for frail older people with non-malignant conditions has potential benefits within community settings, but differ in opinion on the optimal timing and indications for this service. Our findings highlight the importance of consulting all key stakeholders in model development prior to feasibility evaluation

‘My life is a mess but I cope’: An analysis of the language children and young people use to describe their own life-limiting or life-threatening condition

Background: Children and young people with life-limiting and life-threatening conditions have multidimensional needs and heterogenous cognitive and communicative abilities. There is limited evidence to support clinicians to tailor their communication to each individual child. Aim: To explore the language children and young people use to describe their own condition, to inform strategies for discussing needs and priorities. Design: Positioned within a social constructivist paradigm, a secondary discourse analysis of semi-structured interview data was conducted incorporating the discourse dynamics approach for figurative language. Setting/participants: A total of 26 children and young people aged 5–17 years with life-limiting or life-threatening conditions (6 cancer; 20 non-cancer) were recruited from nine clinical services (six hospitals and three hospices) across two UK nations. Results: The language children and young people use positions them as ‘experts in their condition’. They combine medical terminology with their preferred terms for their body to describe symptoms and treatments, and use comparatives and superlatives to communicate their health status. Their language depicts their condition as a ‘series of (functional and social) losses’, which single them out from their peers as ‘the sick one’. Older children and young people also incorporate figurative language to expand their descriptions. Conclusion/discussion: Children and young people can provide rich descriptions of their condition. Paying attention to their lexical choices, and converging one’s language towards theirs, may enable more child-centred discussions. Expanding discussions about ‘what matters most’ with consideration of the losses and differences they have experienced may facilitate a fuller assessment of their concerns, preferences and priorities

Design and Administration of Patient-Centred Outcome Measures: The Perspectives of Children and Young People with Life-Limiting or Life-Threatening Conditions and Their Family Members

Background: Self-reported health data from children with life-limiting conditions is rarely collected. To improve acceptability and feasibility of child and family-centred outcome measures for children, they need to be designed in a way that reflects preferences, priorities and abilities. Objectives: The aim was to identify preferences for patient-reported outcome measure design (recall period, response format, length, administration mode) to improve the feasibility, acceptability, comprehensibility and relevance of a child and family-centred outcome measure, among children with life-limiting conditions and their family members. Method: A semi-structured qualitative interview study seeking the perspectives of children with life-limiting conditions, their siblings and parents on measure design was conducted. Participants were purposively sampled and recruited from nine UK sites. Verbatim transcripts were analysed using framework analysis. Results: A total of 79 participants were recruited: 39 children aged 5–17 years (26 living with a life-limiting condition; 13 healthy siblings) and 40 parents (of children aged 0–17 years). Children found a short recall period and a visually appealing measure with ten questions or fewer most acceptable. Children with life-limiting conditions were more familiar with using rating scales such as numeric and Likert than their healthy siblings. Children emphasised the importance of completing the measure alongside interactions with a healthcare professional to enable them to talk about their responses. While parents assumed that electronic completion methods would be most feasible and acceptable, a small number of children preferred paper. Conclusions: This study demonstrates that children with life-limiting conditions can engage in communicating preferences regarding the design of a patient-centred outcome measure. Where possible, children should be given the opportunity to participate in the measure development process to enhance acceptability and uptake in clinical practice. Results of this study should be considered in future research on outcome measure development in children