Separation and comorbidity of hyperactivity and conduct disturbance in Chinese schoolboys.

In a two-stage community study of 3069 Chinese schoolboys in Hong Kong, those entering stage 2 were classified by scores on Rutter's teacher and parent questionnaires into: (1) a mixed hyperactive/conduct-disturbed (HA-CD) group; (2) a pure hyperactive (HA) group; (3) a pure conduct-disturbed (CD) group; and (4) a normal control group. The four groups of children were compared on a series of psychosocial, cognitive and neurodevelopmental measures. This was followed by a regression analysis to examine the specificity of the differential patterns of associations between HA and CD. There was a mix of negative and positive findings defying a simple, definitive conclusion. However, the positive findings that did emerge supported a growing body of recent literature which favoured a separation of HA from CD and their cross-cultural validity: the former was associated with neurodevelopmental impairments, the latter with family disharmony. The mixed condition, HA-CD, was a hybrid of its two constituent conditions, displaying the attributes of both.

Establishing the constructs of childhood behavioral disturbances in a Chinese population: a questionnaire study.

The behavioral problems of Chinese children were examined in a questionnaire study of a representative sample of 3,069 seven-year-old Chinese schoolboys in Hong Kong using Rutter's questionnaires for completion by parents and teachers. Separate robust dimensions of hyperactivity, antisocial, and neurotic behaviors were evident. The correlations among different dimensions were similar to those reported in the West. Short-term longitudinal analysis suggested that these dimensions were stable over time and that antisocial behaviors might develop in hyperactive children. The finding highlights the necessity of differentiating the hyperactive domain from the antisocial one. A significant source effect was found in all three dimensions. Chinese schoolboys had nearly two times the level of questionnaire-rated hyperactivity compared with school boys in the West; but it is premature to conclude that hyperactivity is more common in Chinese schoolboys in Hong Kong. Cross-cultural differences in adults' expectations and tolerance remain a plausible explanation.

The diagnosis and prevalence of hyperactivity in Chinese schoolboys.

BACKGROUND: This study was undertaken to examine the validity of different diagnostic definitions of hyperactivity in a Chinese population. Estimates of the prevalence of hyperactivity were made according to these different diagnostic definitions. METHOD: In a two-stage epidemiological study of hyperactivity in Hong Kong, 3069 Chinese schoolboys were screened by questionnaires; and a stratified sample of 611 of them entered a second stage for more detailed diagnostic assessment. RESULTS: Children with hyperkinetic disorder (ICD-10) or ADDH (DSM-III) both displayed significant hyperactive symptoms, but with somewhat different external correlates; hyperkinetic disorder tended to show more neurodevelopmental impairments, ADDH more cognitive and educational difficulties. These findings raise the possibility of heterogeneity in the disorders present with hyperactivity. The DSM-III-R category of ADHD was more common, and those extra cases, that did not overlap with ADDH or hyperkinetic disorder, included children with no obvious behavioural, cognitive or neurodevelopmental impairments. Hence ADHD may be an over-inclusive category. Prevalence rates for hyperkinetic disorder, ADDH and ADHD were respectively 0.78%, 6.1% and 8.9%. CONCLUSIONS: A disorder of hyperactivity does exist in the Chinese culture, displaying the same kinds of symptomatology and external correlates as in the West. The prevalence rates of hyperkinetic disorder and ADDH in Chinese schoolboys are on the low side when compared to those reported in Western studies.

Situational versus pervasive hyperactivity in a community sample.

Groups of home and school situational hyperactive primary schoolboys identified from the community were compared with pervasive hyperactive and non-hyperactive controls on a wide range of measures. The hyperactive groups tended to persist in the same category over a half-year period. Both situational hyperactive groups had lower measured activity levels than the pervasive hyperactive group and only the latter differed from non-hyperactive controls. Home hyperactivity was characterized by poor family relationships and was not distinguishable from non-hyperactive home-antisocial controls. School hyperactive boys had specific correlates of low intelligence, motor clumsiness, poor reading and academic abilities. Pervasive hyperactive subjects differed from both situational groups in showing a higher percentage of delayed language development. While home hyperactivity has dubious identity, the distinct pattern of external correlates in school and pervasive hyperactivity speak for the need to regard these as separate entities.

Peak oxygen uptake of 12-18-year-old boys living in a densely populated urban environment.

The purposes of this study were to provide data on the peak VO2 of 12-18-year-old boys from Hong Kong, a densely populated urban environment; to compare these data with those for other similarly aged populations; and to examine the correlations between peak VO2 and various anthropometric parameters of this group. A stratified, random sample of 86 ethnic Chinese boys had their peak VO2 determined using an on-line gas analysis system during incremental, treadmill running. The mean peak VO2 of the boys was 2.7 SD 0.44 l.min-1 or, when expressed in relation to body mass, 52.0 SD 5.8 ml.kg-1.min-1. Peak VO2 (l.min-1) was significantly correlated with body mass (r = 0.72, p < 0.001, age (r = 0.49, p < 0.001) and height (r = 0.71, p = 0.001). Peak VO2 (ml.kg-1.min-1) showed no correlation with age or height. These data suggest that this population group has peak VO2 values very similar to those observed in boys from most other population groups.

A comparison of three induction agents in paediatric anaesthesia--cardiovascular effects and recovery.

We studied 30 children undergoing circumcision randomly allocated to receive either thiopentone 4 mg.kg-1, propofol 2.5 mg.kg-1 or midazolam 0.5 mg.kg-1 (n = 10) IV over 30 seconds at induction of anaesthesia. Blood pressure and pulse rate during the first 15 minutes of induction were recorded by a Finapres 2300e and a Cardiocap CM-104, and changes from preinduction baseline compared between the three induction agents and the two recording instruments. Postoperatively, blood levels of the induction agents were measured and recovery from anaesthesia was assessed by clinical criteria, mood and sedation scores and psychomotor performance. The Cardiocap data revealed no statistically significant haemodynamic differences between the three induction agents. Finapres data demonstrated that propofol caused a greater decrease in mean arterial pressure when compared to thiopentone at one minute (P = 0.01) and the MAP remained significantly lower than midazolam at five minutes (P = 0.02), illustrating an advantage of continuous over intermittent non-invasive blood pressure monitoring. The midazolam group took longer to identify themselves compared to both the propofol (P = 0.005) and the thiopentone groups (P = 0.02), but there was no difference in the groups in time to eye-opening. Psychomotor performance on awakening was significantly worse in the midazolam group compared to the propofol (P < 0.03) and thiopentone groups (P < 0.02). Most children had recovered to 80% of their best, practised, unmedicated, preoperative performance four hours after awakening, irrespective of the induction agent administered. Drug blood levels correlated weakly with both methods of psychomotor assessment (r > or = 0.6). Of the three induction agents, thiopentone caused the least haemodynamic perturbation on induction, and anaesthesia induced with midazolam caused the greatest psychomotor impairment on awakening. Within one hour patients in all drug groups were equally awake, co-operative and co-ordinated.

Preoperative and postoperative oxygen saturation in the elderly following spinal or general anaesthesia--an audit of current practice.

We have compared the incidence of preoperative and postoperative oxygen desaturation in 20 elderly patients undergoing dynamic hip screw insertion for fractured neck of femur, allocated randomly to two groups to receive subarachnoid anaesthesia (SA, n = 10) or a general anaesthetic (GA, n = 10). Oximetry data were recorded during the preoperative night and the first 48 hours after surgery using Satmaster. Data associated with zero amplitude signal were automatically invalidated by the software and decreases in SpO2 which were preceded by contemporaneous changes in signal amplitude which conformed to a previously described template were assumed to be artefactual and were discarded from final data analysis. Data demonstrated a wide interpatient variability. However, those patients who desaturated preoperatively continued to do so in the postoperative period. The differences between the preoperative and postoperative oximetry profiles were examined for each patient and demonstrated a significantly longer time spent with SpO2 < 90% in the GA group compared with the SA group, in all the recorded time periods, except on the day of surgery. The SA group showed an improvement in oxygen saturation postoperatively when compared to the preoperative night, spending less time with an SpO2 < 85%. We conclude that the subarachnoid anaesthetic technique was associated with a lower incidence of postoperative oximetry desaturation when compared with general anaesthetic for these elderly patients undergoing repair of fractured neck of femur.

Use of two oximeters to investigate a method of movement artefact rejection using photoplethysmographic signals.

Oxygen haemoglobin saturations and plethysmograph signal amplitudes were recorded from two oximeters placed on the fingers and toes of 10 patients undergoing oesophagectomy, to assess a method of removing motion artefact from saturation recordings. By examining changes in the plethysmograph amplitude that preceded changes in saturation, episodes of desaturation caused by movement artefacts were removed from the data. The reliability of the method was then determined by scrutinizing two concurrent oximetric profiles from each patient. A total of 1600 h of data were evaluated. Desaturations occurring contemporaneously in both oxygen saturation profiles were presumed genuine, whereas a desaturation occurring in only one of the profiles was classified as artefactual. Our method had a sensitivity of 96%, a positive predictive power of 98% and a specificity of 60%. We modified the method to increase specificity and re-evaluated our data. We found that a useful increase in specificity was associated with a considerable decline in sensitivity.

A comparative study of computed tomographic and plain radiographic methods to measure vertebral rotation in adolescent idiopathic scoliosis.

A comparative analysis of two methods of measuring vertebral rotation in adolescent idiopathic scoliosis is reported in this article. Nash and Moe's pedicle shift method (using plain anteroposterior radiographs) is compared with a new method using computed tomographic scans. The computed tomographic scans of the whole length of the major curve and the scout films obtained from seventeen girls aged 12.5-14 years were measured for rotation of each vertebra of the curve (total number of vertebrae measured by two methods = 173). This study has three interesting new findings: 1) Those vertebrae with Nash & Moe grade 0 had up to 11 degrees of vertebral rotation when measured using the computed tomographic method. Therefore, Nash & Moe's grade '0' is not a neutrally rotated vertebra; 2) For Nash & Moe grade 1 and 2, the computed tomographic method revealed statistically significantly greater rotation for lumbar vertebrae than thoracic vertebrae. There was a similar pattern for Nash & Moe grade 0 but these differences were not statistically significant; and 3) Simple formulae are reported to convert Nash & Moe's grades into angle of vertebral rotation as obtained by CT method separately for thoracic and lumbar vertebrae.

Cognitive-behavioural group therapy for Hong Kong Chinese adults with mental health problems.

Ninety-one Chinese in the community, aged between 18 and 45, with mental health problems ranging from mild to moderate degree, were treated by cognitive behavioural group therapy (CBGT) for a period of 3 months. All subjects were assessed on multiple measures at 4 time points: screening, pre-treatment (after 3 months), post-treatment and at 3-month follow-up. Attendance was good. A standard practice manual was developed to ensure consistent treatment by 2 group workers. After controlling for the placebo effect in the waiting period, treatment effect was demonstrated which was sustained after a three month period. The all-round improvement included a decrease in psychiatric symptoms, improvement in self-assessment, better and more social activities and being more able to cope with problems. In terms of psychiatric diagnosis, depressed subjects gained the most benefit and personality disorder subjects the least. Parents seemed to benefit more than non-parents.

Antagonism of the hypnotic effect of midazolam in children: a randomized, double-blind study of placebo and flumazenil administered after midazolam-induced anaesthesia.

In a randomized, double-blind study, we administered placebo and flumazenil to 40 healthy Chinese boys, aged 3-12 yr, undergoing circumcision. The children received midazolam 0.5 mg kg-1 orally for premedication and 0.5 mg kg-1 i.v. during induction. After operation the patients were given 0.1 ml kg-1 of a blinded solution followed by 0.05 ml kg-1 min-1 until either they awoke or the 10-ml ampoule of solution was empty. Efficacy of antagonism of midazolam was assessed by times to eye opening and self identification, modified Steward coma scale, a post-box toy completion-time ratio and qualitatively by an independent observer. The difference between flumazenil and placebo was both clinically and statistically different in the first 2 h. Children receiving flumazenil awoke approximately four times faster and identified themselves nearly three times sooner; 65% of this group could complete the post-box toy at 10 min, compared with none of the placebo group. There were no cases of resedation, but one child did not awaken for 30 min after i.v. administration of flumazenil 1.0 mg. The mean total dose of flumazenil administered was 0.024 (SD 0.019) mg kg-1. Flumazenil rapidly antagonized midazolam-induced hypnosis in children and was associated with minimal change in cardiorespiratory variables.

The structure and prevalence of behavioral problems in Hong Kong preschool children.

Nearly all 3-year-old Chinese children in Hong Kong attend preschool facilities, making it possible to study their behavior in a group learning situation based upon teachers' perception. The Preschool Behavior Checklist (PBCL), a teacher's questionnaire, was applied to a random sample of 851 Chinese children, ages 36 to 48 months. The factor structure of the PBCL was very similar to that obtained from its original British study, supporting its usage cross-culturally. Prevalence of behavior disorder was high as defined by the PBCL. This reflected specific cultural demands at school settings. Significant sex differences were also found in the overall rate of behavior disorder and symptom patterns. As in other studies, boys had more hyperactive, conduct, and speech problems. The results suggested a certain degree of universality of symptomatology for children at the preschool level.

Behaviour disorder in pre-school children in Hong Kong. A two-stage epidemiological study.

A representative sample of 855 Hong-Kong Chinese children aged 36-48 months were assessed using the BSQ and the PBCL. Good reliability for both instruments were found. For the BSQ and PBCL, 12.75% and 27.5% were above the cut-off points of 10+ and 12+ respectively and 5.9% were above both cut-off points. In the second stage, 234 subjects were recruited by stratified random sampling according to the results of the screening state. A clinician interviewed the parent, child and teacher before making a diagnosis. The prevalence of behaviour disorder was: nil, 53.7%; dubious, 23.1%; mild, 18.0%; moderate, 4.5%; and severe, 0.7%. There were significantly more boys in the categories mild, moderate and severe.

Screening for congenital hypothyroidism in Hong Kong.

A pilot cord blood TSH screening program for congenital hypothyroidism was commenced in Hong Kong in April 1982. By April 1984, 14 411 neonates born in two hospitals were screened for this disorder. Five cases of primary hypothyroidism and two cases of transient hypothyroidism were detected. The detection of cases of congenital hypothyroidism with only moderately elevated cord blood TSH values means that the recall rate will remain high.