Biomedical subjects

R G Knight

Publications and source records attributed to R G Knight.

At least 19 recordsLinked to original sources

PubMed2001

Sun protection practices, knowledge and attitudes to tans among New Zealand adolescents, 1991-1997.

AIMS: To examine change in the self-reported sun protection, knowledge and attitudes to tans amongst fourth form students from 1991 to 1997. METHODS: Questionnaires were mailed to 20 New Zealand secondary schools, where 20 students were randomly selected to participate in each school. RESULTS: The proportions of adolescents who reported getting sunburnt over summer, and sunbathing for the purpose of tanning increased significantly from 1991 to 1997, while there were decreases in the proportions who reported getting a suntan, wearing clothing for sun protection and having heard of melanoma. There was also some evidence of a decrease in the attribution of positive qualities to a tan. CONCLUSIONS: Some positive changes in attitudes to tanning among New Zealand adolescents were present over the 1991-1997 period. Although these changes are promising there was little change in utilisation of sun protection measures, in fact, there was evidence that this had worsened.

Adolescent↗

PubMed2001

Automatic hypermnesia and impaired recollection in schizophrenia.

Evidence from studies of nonmnemonic automatic cognitive processes provides reason to expect that schizophrenia is associated with exaggerated automatic memory (implicit memory), or automatic hypermnesia. Participants with schizophrenia (n = 22) and control participants (n = 26) were compared on word stem completion (WSC) and list discrimination (LD) tasks administered using the process dissociation procedure. Unadjusted, extended measurement model and dual-process signal-detection methods were used to estimate recollection and automatic memory indices. Schizophrenia was associated with automatic hypermnesia on the WSC task and impaired recollection on both tasks. Thought disorder was associated with even greater automatic hypermnesia. The absence of automatic hypermnesia on the LD task was interpreted with reference to the neuropsychological bases of context and content memory.

Adult↗

PubMed2001

Caregiver depression following traumatic brain injury (TBI): a consequence of adverse effects on family members?

Many studies have demonstrated that the behaviour of individuals with traumatic brain injury (TBI) predicts the emotional adjustment of their caregivers. The primary objective of the present study was to obtain an understanding of potential moderating and mediating variables between carer depression and analogous stressors. Seven sets of predictor variables (demographic variables, concurrent stressful life events, behavioural problems, social role problems, extent of adverse effects on family members, appraisal, and support) and the criterion variable of depression in caregivers were examined. Fifty-eight carers participated in the study at 6 months, 1 year, 2 years, or 3 years following injury. The number of adverse effects on family members (other than the informant) was the only stressor significantly related to carer depression. However, carer appraisal of adverse family effects was found to mediate the relationship between stressor and depression, and carer perception of support effectiveness was found to moderate the effect of adverse family effects on depression. Forty-six per cent of the variance in caregiver depression was accounted for by carers appraisal of adverse family effects and the interaction of adverse family effects and support effectiveness. These findings highlight the importance of supporting families as a whole in the rehabilitation of persons with TBI.

Activities of Daily Living↗

PubMed2001

Sunburn and sun protection among New Zealand adolescents over a summer weekend.

OBJECTIVE: To examine predictors of sunburn and sun protection practices during summer weekends within a sample of NZ adolescents. METHOD: Phone interviews were conducted with 203 participants aged 12-17 years. Questions were asked about behaviour from 11am to 4pm during the previous weekend. RESULTS: Less than half of the sample outside during peak radiation hours wore sunscreen and only a quarter wore hats. Sunburn was experienced by 31% of adolescents and was associated with spending longer times outside and use of sunscreen without reapplication. Wearing a sunhat was predicted by being younger and male, while sunscreen use was predicted by being female. CONCLUSIONS: There is a lack of appropriate sun protection among many NZ adolescents, and correspondingly high rates of sunburn. Possible opportunities to address this are through increasing the efficacy of sunscreen and sun hat use, and creating outdoor environments that support sun avoidance.

Adolescent↗

PubMed2000

A procedure for testing prospective remembering in persons with neurological impairments.

A video-based procedure for assessing prospective remembering (PR) in brain-injured clients is described. In this task, a list of instructions is given, each comprising an action (buy a hamburger) and a cue (at McDonalds), which are to be recalled while watching a videotape segment showing the view of a person walking through a shopping area. A group of 12 clients with varying degrees of memory impairment undergoing rehabilitation completed both a video test and a comparable task in real-life. Significant correlations were found between the two measures, indicating that a video-based analogue can be used to estimate prospective remembering in real life. Scores on the PR task were associated with accuracy of recall on a word-list task, but not with the Working Memory Index of the Wechsler Memory Scale-III, suggesting that the task is sensitive to levels of amnesic deficit.

Adult↗

PubMed1999

Verbal memory in non-demented patients with idiopathic Parkinson's disease.

This study assessed the verbal memory functions of 20 patients with idiopathic Parkinson's Disease (PD) without any clinical evidence of dementia and 20 Medical Control (MC) patients with similar levels of physical disability. Performance was compared on tests of immediate recall, word list learning in intentional and incidental contexts, word completion priming, remote memory, metamemory and awareness of mnestic abilities. Significant differences were found in new learning of verbal material under incidental but not intentional learning conditions. Group differences were also observed on measures of remote memory and metamemory. The groups did not differ in word completion priming performance or recognition memory. These findings are consistent with other evidence suggesting that PD patients without dementia may have subtle cognitive deficits that affect memory performance. These may be attributable to impairments of attention allocation, formulation of retrieval strategies, and effortful learning associated with frontal lobe dysfunction. The group differences could not be attributed to impairments of intellectual functions, verbal fluency, level of physical disability, or mood disturbance.

Aged↗

PubMed1998

Controlled and automatic memory process in Alzheimer's disease.

The aim of this study was to examine the contribution of controlled (or conscious) and automatic (or unconscious) memory processes to the performance of a stem-completion recall task by persons with Alzheimer's disease and a matched group of healthy elderly individuals. The recall task made use of the process dissociation procedure of Jacoby (1991), which allows the separate estimation of conscious and unconscious influences on memory. Recollection was found to be severely impaired in the community dwelling demented patients. Further, the estimates of the automatic processing were also found to be reduced, although there was considerable overlap in the performance of the two groups on this parameter. It was found that the residual capacity of Alzheimer's patients to recall previously learned information was supported to a substantial degree by their automatic memory processes.

Activities of Daily Living↗

PubMed1998

Caregiving and well-being in a sample of women in midlife.

A survey of 742 women in midlife found that 12% were involved in the care of another person with a chronic health disorder. Of note was the diversity of circumstances that led to the women becoming caregivers. Further, about a third of the carers were supporting more than one person. Carers did not differ on measures of depression or subjective health ratings from persons not involved in care. Burden scores were predicted by co-residence, low satisfaction with social support, and poorer health ratings on the part of the carers but not by the relationship between the person cared for and the carer.

Adult↗

PubMed1998

Caring for a family member with a traumatic brain injury.

The responses to a questionnaire on subjective burden are reported for 52 primary caregivers of a group of persons with traumatic brain injuries sustained an average of 6 years previously. The aim of the study was to examine satisfaction with social support, perception of coping skills, and appraisal of symptoms as predictors of strain in the carers. A range of responses, both positive and negative, to the work of caring for a relative with a head injury was reported. A high prevalence rate of emotional and behavioural changes in the persons with head injuries was found and the amount of distress caused by these symptoms was found to be predictive of burden. The other factor important in predicting burden was the carers' ratings of their satisfaction with their ability to cope with the work of caregiving. Social support, injury severity, and the demographic characteristics of the persons with head injury and their carers were not significant predictors. Depression in the carers was also investigated and the variable most predictive of elevated depression scores was coping satisfaction. These findings reinforce the importance of strengthening carers coping resources in rehabilitation work with head injured persons and their families.

Adaptation, Psychological↗

PubMed1997

Psychometric properties of the Centre for Epidemiologic Studies Depression Scale (CES-D) in a sample of women in middle life.

The Centre for Epidemiologic Studies Depression Scale (CES-D) was completed by 675 women taking part in a longitudinal investigation of health-related issues. The data were submitted to confirmatory factor analysis using LISREL 7 and a 4-factor model was found to fit the data moderately well. A second-order depression factor was also identified. The results provide support for the construct validity of the total and subscale scores from this measure. The scale was found to have good reliability. Evidence was found that scores on the subscale measuring somatic features of depression may be inflated in women who have experienced a chronic health problem in the past 12 months.

Adult↗

PubMed1997

Adult age differences in controlled and automatic memory processing.

The memory performance of groups of younger, middle-aged, and older participants was tested on indirect and direct tests of word stem completion and on a process-dissociation task. As expected, on the direct tests of stem completion, older participants had lower scores than the younger and middle-aged groups. Age effects were also found on the indirect word completion test. The process-dissociation task allowed memory performance to be divided into controlled and automatic processing components. Estimates of automatic processing were comparable for the three groups, but there was an age effect for controlled processing, with the middle-aged and older groups differing from the younger group. These results confirm the findings of J. M. Jennings and L. L. Jacoby (1993) and suggest that the decline in conscious processing efficiency begins in middle age.

Adult↗

PubMed1997

Psychosocial consequences of caring for a spouse with multiple sclerosis.

Fifty-five spousal caregivers of persons with multiple sclerosis completed a questionnaire assessing the stress associated with caregiving. They were found to experience a range of negative effects, similar to those reported by other groups of carers of persons with degenerative neurological diseases. The behaviors causing most distress to the carers were associated with motor problems, sudden mood changes, partner upsetting other people, incontinence and pain. Overall, wives had higher burden scores than husbands. This was accounted for primarily by their higher levels of physical distress such as tiredness. Following the stress-appraisal-coping model of Lazarus and Folkman (1984) it was hypothesized that individual differences in burden would be accounted for primarily by the carers' appraisal of the symptoms, perceived social support, and satisfaction with coping. Regression analyses supported the importance of satisfaction with coping and social support as predictors of perceived burden. In addition, life satisfaction was found to be predicted by burden independently of other predictors.

Adult↗

PubMed1996

The Profile of Functional Impairment in Communication (PFIC): a measure of communication impairment for clinical use.

This article describes the construction of the Profile of Functional Impairment in Communication (PFIC), a scale designed for the assessment of communication impairments following traumatic brain injury. The measure comprises 10 feature summary scales, assessing severity of impairment, and 84 specific behaviour items, assessing the frequency of specific communication impairments. To assess the psychometric properties of the scale, videotaped dyadic social interactions of 20 patients with traumatic brain injury were rated by eight trained raters. The feature summary scales were found to have acceptable inter-rater reliabilities, and high concurrent validity and internal consistency. Four case descriptions are presented to illustrate the clinical application of the PFIC. It is concluded that the PFIC is a useful measure for the identification of specific communication impairments in clinical practice.

Adolescent↗

PubMed1994

Priming deficits in patients with dementia of the Alzheimer type.

In a study that replicated the procedures used by Salmon et al. (1988), the effect on stem completion performance of two different semantic orientation tasks has been assessed in patients with Alzheimer's disease. Previously reported findings of impairment in repetition priming in Alzheimer patients were confirmed. Performance was not affected by the nature of the orientation task. No significant correlations were found between explicit and implicit memory tests. The results are discussed in the context of a hypothesized parallel decline in explicit and implicit memory systems.

Aged↗

PubMed1994

Differential relationships between stress and disease activity for immunologically distinct subgroups of people with rheumatoid arthritis.

Immunologically distinct subgroups of patients with rheumatoid arthritis (RA)--those with the autoantibody rheumatoid factor (seropositive RA) and those without (seronegative RA)--were compared on a variety of clinical and self-report measures in a consecutive series of women with disease of 7 years' or less duration. The groups were comparable on clinical, pain, functional, and psychosocial variables. However, the seronegative RA group reported elevated levels of preonset negative life event stress. Postonset life event stress and disease activity were significantly correlated for the seronegative RA group, but not for the seropositive RA group. Results suggest that stress factors may be more important in the etiology and maintenance of seronegative RA and that the seronegative RA group may possibly derive particular benefit from psychological techniques to enhance stress management skills.

Adult↗

PubMed1993

Neuropsychological impairment and return to work following severe closed head injury: implications for clinical management.

AIMS: To study the rate and timing of return to work following severe closed head injury, and to compare the neuropsychological functioning of patients who successfully return to work with that of patients who fail to return to work. METHODS: The vocational status, level of cognitive functioning and personality functioning of a consecutive series of 66 patients who survived severe closed head injury was assessed between six months and three years postinjury. The level of cognitive and personality functioning of patients who returned to work were compared with that of patients who failed to return to work. RESULTS: Twenty five percent of patients failed to return to work, and a further 17% returned to work under special conditions of employment. Failure to return to work was related to the degree of neuropsychological impairment (cognitive deficit and adverse personality change), injury severity (duration of posttraumatic amnesia), and age. Multiple regression analysis found the total number of neuropsychological symptoms to be the strongest predictor of the patients' return to work. CONCLUSIONS: These findings suggest that neuropsychological symptoms are the main mechanism through which severe brain injury affects the ability to return to work. It is recommended that vocational rehabilitation of severe closed head injury patients be based on a comprehensive neuropsychological assessment.

Adolescent↗

PubMed1993

Course of insight disorder and emotional dysfunction following closed head injury: a controlled cross-sectional follow-up study.

Closed-head injury (CHI) patients at either 6 months (n = 24), 1 year (n = 19), or 2 to 3 years (n = 23) postinjury, were compared with a group of orthopedic control (OC) patients (n = 27). CHI patients assessed at 6 months postinjury experienced a Post-Traumatic Insight Disorder, in which they underreported the severity of their behavioural impairments. CHI patients in the 1 year and 2 to 3 year follow-up groups evidenced both greater insight about their level of behavioural impairment, and higher levels of emotional dysfunction. These findings suggested that the return of insight is associated with increased risk for emotional dysfunction. Implications of these findings for assessment and treatment of closed-head injury patients are discussed.

Adolescent↗

PubMed1993

A self-report articular index: relationship to variations in mood and disease activity measures.

Self-report can provide an inexpensive method for monitoring disease activity or treatment response in RA, but may be affected by confounding variables such as the patient's mood. The relationship of a self-report articular index (AI) to other relevant parameters was assessed from data gathered at approximately monthly intervals from 16 women with RA. Statistical analysis showed that the AI covaried most strongly with other measures of disease activity and functional disability, while mood variables and ESR covaried separately. These results indicated that responses on the self-report AI paralleled disease activity, and were not merely an artifact of variations in the patient's mood.

Adult↗