Dutch norms for the Strengths and Difficulties Questionnaire (SDQ) - parent form for children aged 2-18 years.

BACKGROUND: Identification of children at risk for psychosocial problems is important to be able to provide supportive and tailored care at an early stage. Due to its brevity and wide age range, the Strengths and Difficulties Questionnaire (SDQ) Parent Form is an appropriate instrument for use in paediatric clinical practice as it facilitates assessment of psychosocial functioning from young childhood into adulthood. The aim of the present study was to provide Dutch normative data for the SDQ Parent Form. METHODS: A sample of 1947 parents with children aged 2-18 years was drawn from a large panel of a Dutch research agency, stratified on Dutch key demographics of the parents. The SDQ Parent Form assesses the child's Emotional symptoms, Conduct problems, Hyperactivity-Inattention, Peer problems and Prosocial behaviour. Summary scores can be calculated: Internalising, Externalising and Total difficulties. Internal consistency (Cronbach's alpha coefficient) and normative scores (mean, median, clinical cut-off scores) of the SDQ- Parent Form were calculated in four age-groups 2-3, 4-5, 6-11 and 12-18 years. Gender differences were tested with independent t-tests. RESULTS: A total of 1174 parents (60.3%) completed the SDQ. In the age-groups 2-3 and 4-5, norm scores are not available for Conduct problems and Peer problems due to insufficient internal consistency. In addition, in age-group 2-3, norm scores for Emotional symptoms and Internalising are not available because of insufficient internal consistency. In the age-groups 6-11 and 12-18, norm scores are available for all scales, with Cronbach's alpha coefficients 0.53-0.86. The comparison by gender revealed that boys had more behavioural problems than girls (0.000 < p < 0.048), most prevalent for Hyperactivity-Inattention, Peer Problems, Prosocial behaviour, Externalising and Total Difficulties. CONCLUSIONS: Dutch normative data by age-group and gender are now available for parent-reported SDQ scores in children aged 2-18 years. Due to insufficient internal consistency, normative scores for 2-5 year-old children could not be presented for several SDQ scales. Yet, the SDQ Total score provides a reliable indication of the psychosocial functioning of younger children. In case of high Total scores in children younger than 6 years, alternatively to scale scores, the answers on the individual items could yield useful clinical information about the child's problems.

Health related quality of life in Dutch infants, toddlers, and young children.

BACKGROUND: The purpose of this study is to provide Dutch normative data and to assess internal consistency and known-groups validity for the TNO AZL Preschool Children Quality of Life (TAPQOL) and the acute version of the generic Pediatric Quality of Life Inventory (PedsQL 4.0) in Dutch young children aged 0-7 years. METHODS: Participants were selected from a panel of a large Dutch market research agency. A sample of 794 parents (response rate 61%, 39% fathers) of children (53% boys) from the general Dutch population, completed an electronic version of the TAPQOL (N = 227 infants aged 0-1 years) or PedsQL 4.0 (N = 293 toddlers aged 2-4 years and N = 274 young children aged 5-7 years). RESULTS: Except for the 'stomach' scale (α = .39), the TAPQOL showed acceptable to excellent internal consistency (α = .60-.88). The PedsQL 4.0 showed acceptable to excellent reliability in children aged 2-4 years (α = .60-.88) and in children aged 5-7 years (α = .76-.90). Children with a chronic health condition had lower scores than healthy children on 3 out of 12 domains of the TAPQOL (p = .001-.013) and on 2 out of 6 domains of the PedsQL 4.0 for children aged 2-4 years (p = .016-.04). The PedsQL 4.0 differentiated on all domains (p < .05) between children aged 5-7 years with and without a chronic health condition. CONCLUSION: In Dutch children aged 0-7 years old, HRQoL can be relialy measured with the TAPQOL and the PedsQL 4.0. However, it remains unclear whether these HRQoL instruments can distinguish between healthy children and children with a chronic health condition under the age of 5.

Anxiety and depression in mothers and fathers of a chronically ill child.

We aimed to determine the levels of anxiety and depression in mothers and fathers of a chronically ill child (0-18 years) and to study which parental and child variables are associated with anxiety and depression. In a cross-sectional design, anxiety and depression were assessed with the Hospital Anxiety and Depression Scale. Scores were compared to a Dutch reference group by analysis of variance and logistic regression analysis. Linear regression analyses were performed to examine which variables were associated with anxiety and depression. Mothers of a chronically ill child (n = 566) scored significantly higher than the reference group (p < .001) on anxiety (Mean 5.9 vs 4.8) and depression (Mean 4.5 vs 3.1). Fathers (n = 123) had higher depression scores (Mean 4.5 vs 3.6; p < .05), but fathers' anxiety scores were comparable to the reference group. The percentages of mothers in the clinical range of anxiety (31.8 vs 20.7 %, OR 2.03, 95 % CI 1.46-2.83) and depression (23.0 vs 12.0 %, OR 2.76, 95 % CI 1.84-4.13) were higher (p < .001) than in the reference group. No differences were found for fathers in the clinical range for anxiety and depression. Practical problems in daily life (a: ß = .33, d: ß = .25) and parenting stress (a: ß = .30, d: ß = .32) showed the strongest association with anxiety and depression for parents as a group. Illness-related characteristics of the child were not related. Parents of a chronically ill child, especially mothers, reported high levels of anxiety and depression. Awareness about parental anxiety and depression in pediatrics is important as well as targeted interventions.

Stressors and alcohol consumption.

The objective of this study was to examine the relationship between negative life events and chronic stressors and drinking behaviour. Data suggested that some life events (getting divorced) and some chronic stressors (financial difficulties, unfavourable marital status, and unfavourable employment status) were positively related to abstinence among men and women. Furthermore, some life events (being a victim of a crime, decrease in financial position, divorce or reporting two or more life events) were positively associated with heavy drinking among men. Chronic stressors, such as unfavourable marital status and unfavourable employment status, were also related to heavy drinking among both men and women. Results presented here suggest that people under stressful conditions are more likely to either abstain or drink heavily rather than to drink lightly or moderately.

Persistent effects of maternal deprivation on HPA regulation can be reversed by feeding and stroking, but not by dexamethasone.

Maternal deprivation of neonatal rats for 24 h has immediate and persistent effects on hypothalamic-pituitary-adrenal (HPA) regulation. Immediately after deprivation corticosterone (CORT) is elevated. The primary purpose of our experiments was to determine if, by preventing this CORT elevation, the persistent effects could be reversed. In experiment 1, pups were injected with dexamethasone at the onset of the 24-h deprivation period on postnatal day 11 to suppress the rise in CORT. In experiment 2 some aspects of maternal behaviour known to suppress CORT levels were mimicked during deprivation from postnatal days 11-12. The pups were either: (1) left undisturbed; (2) stroked periodically; or (3) stroked and episodically fed. At postnatal day 20 basal and stress-induced adrenocorticotrophic hormone (ACTH) and CORT levels were measured as well as brain mineralocorticoid (MR) and glucocorticoid receptors (GR). Neonatal rats receiving dexamethasone prior to the onset of the deprivation on day 11 did not differ on day 20 from deprived pups that were exposed to elevated CORT levels. There were no detectable changes in the non-deprived pups that were treated with dexamethasone. In contrast, feeding and stroking during the period of deprivation obliterated the persistent effects both with regard to the reduced ACTH response and the decreased GR mRNA in hippocampus and hypothalamus. Stroking alone appears to have no influence. In conclusion, the persistent reduction of the ACTH response to mild stress and the decrease of GR mRNA is not mediated by deprivation-induced elevations in CORT, but appears to be reversible by reinstating specific aspects of the dam's nurturing behaviour.

Aggregate comparisons of self-reported versus nonself-reported drinking in a general population survey.

Insight is gained into the validity of self-reported drinking in the general population by comparing self-reports and nonself-reports on the aggregate level. Married and cohabiting respondents of a general population survey (N = 2,169) were asked about both their own and their spouses' drinking behavior. It was found that on the aggregate level, distribution of "moderate" drinking and usual frequency of drinking is similar between self- and nonself-reports. Self-reported "heavy" drinking, however, is lower than nonself-reported "heavy" drinking among women in general, older women, and women with a lower education. Among men in general and older men in particular, however, self-reported occasional "heavy" drinking was found to be higher. The similar distribution of "moderate" drinking and usual frequency of drinking between self- versus nonself-reports gives reassurance about the validity of self-reported drinking behavior. The discordance in self-reported versus nonself-reported "heavy" drinking, however, raises questions about the validity. Interpretation of the discordance is not conclusive: more research (experimental and qualitative) has to be done to disentangle this issue.

Cervical cancer screening: spatial associations of outcome and risk factors in Rotterdam.

OBJECTIVE: Obtaining insight into the geographic distribution of attendance and smear test results at the cervical cancer screening program in Rotterdam neighbourhoods, associated with socio-economic status, marital status and the percentage migrants. DESIGN: Ecological analysis was carried out on data on cervical cancer screening outcome and population figures, provided by the Rotterdam Local Health Information System, in which health information is collected at neighbourhood level. SETTING: The cervical cancer screening program in the city of Rotterdam. PARTICIPANTS: Fifty-three neighbourhoods, with overall 569,105 inhabitants, of whom 70,621 women between 1992 and 1994 were invited for the screening program. MAIN RESULTS: Between neighbourhoods a large difference in attendance rate and the percentage positive smears exists. A high socio-economic level of a neighbourhood, and a low percentage migrants, single or divorced women correspond with high attendance. A high socio-economic status of a neighbourhood and a low percentage migrants correspond with a low percentage smear test Pap 3B or higher. Socio-economic status, percentage migrants and marital status are highly interrelated on neighbourhood level. Multivariate analysis showed a negative correlation between the attendance rate and the percentage of single and divorced women, and a positive correlation between the percentage migrants and the percentage of positive smears (Pap 3B or higher). CONCLUSION: Various risk groups, showing low attendance or a high percentage of positive smears, are clustered in neighbourhoods and can be identified by socio-economic status, marital status and nationality. Activities to improve attendance can be focused towards these neighbourhoods.

Early vs. late maternal deprivation differentially alters the endocrine and hypothalamic responses to stress.

Twenty-four hours of maternal deprivation results in persistent changes in the ACTH response to mild stress. These effects are dependent on the age of the neonate at the time of deprivation. Pups that were separated from the dam at postnatal days (pnd) 3-4 showed an enhanced stress-induced ACTH response at age 20, while pups deprived at pnd 11-12 displayed an attenuated ACTH response to stress at that time. The present study was designed to test the hypothesis that the immediate effects of deprivation at pnd 3 vs. pnd 11 would provide an explanation for these paradoxical effects observed at day 20. For this purpose, we measured the basal and the stress-induced ACTH and corticosterone (CORT) response at days 4 and 12, following 24 h of maternal deprivation. Furthermore, we examined whether similar differences in c-fos and CRH mRNA expression in the paraventricular nucleus (PVN) accompanied the differences in response characteristics of ACTH at pnd 20. The results indicate that changes in the ACTH and CORT responses were minimal after 24 h of maternal deprivation at day 4, whereas these hormones were markedly elevated following deprivation at day 12. The persistent effects also showed age-dependency: pups deprived early showed at pnd 20 an exaggerated ACTH response. Late deprived juveniles exhibited an attenuated ACTH response to stress at pnd 20 while in both conditions the CORT response was not different from the non-deprived litter mates. These persistent endocrine changes were accompanied by the changes in the neural stress markers. The expressions of c-fos and CRH mRNA in the PVN were at pnd 20 significantly greater in their controls in early-deprived animals. The late deprived juveniles showed a reduced response in these neural markers. In conclusion, the persistent alterations in ACTH are reflected by changes in c-fos and CRH mRNA, but these changes in endocrine and in neural stress markers do not appear to be related to any of the hormonal changes that occur at the time of maternal deprivation.

Maternal deprivation effect on the infant's neural stress markers is reversed by tactile stimulation and feeding but not by suppressing corticosterone.

After 24 hr of maternal deprivation, significant elevations in ACTH and the naturally occurring glucocorticoid corticosterone (CORT) are observed during the stress-hyporesponsive period. The deprived pups also showed in the paraventricular nucleus (PVN) a marked increase of stress-induced c-fos mRNA and a reduction of corticotropin-releasing hormone (CRH) and glucocorticoid receptor (GR) mRNA; in hippocampal CA1, a reduction of the mineralocorticoid receptor (MR) and GR was observed. Here, we examined whether these changes are reversed by (1) preventing the elevations of CORT characteristic for the 11-d-old deprived pups by administering the synthetic glucocorticoid dexamethasone (DEX); or (2) reinstating some aspects of maternal behavior. The pups were either (1) left undisturbed, (2) stroked, or (3) stroked and episodically fed by cheek cannulation. At postnatal day 12, peripheral and neural stress markers were measured. Nondeprived animals served as controls. Experiment 1 demonstrates that although CORT was kept low by DEX, the central effects on CORT receptors, CRH, and c-fos mRNA were still present, except for MR in hippocampal CA1. Experiment 2 shows that stroking alone prevented the stress-induced rise in ACTH and c-fos mRNA and in the reduction in CRH and MR mRNA. In pups that were fed and stroked, CORT and GR mRNA resembled nondeprived controls. In conclusion, the changes in peripheral endocrine responses and in the brain cannot be attributed to the effect of elevated CORT concentrations, which are characteristic of the maternally deprived neonate. However, reinstating some components of the dams' nurturing behavior can reverse the effects evoked by maternal deprivation.

The ontogeny of glucocorticoid negative feedback: influence of maternal deprivation.

Glucocorticoid feedback can be viewed as having two modes of operation: proactive and reactive. "Proactive" feedback maintains basal activity of the hypothalamic-pituitary-adrenal axis, whereas the termination of stress-induced hypothalamic-pituitary-adrenal activity is facilitated by "reactive" feedback. In the present study we studied the ontogeny of both feedback modes and tested the hypothesis that the development of feedback depends on mother-pup interaction. On postnatal day 9 or 12, pups were deprived (DEP) of the dam for 24 h; nondeprived pups of the same age served as controls. The pups were adrenalectomized (ADX) at the end of deprivation and given corticosterone (CORT) replacement by either injection or pellet implants using the following two designs: first at the time of adrenalectomy (ADX) to test the role of CORT in the maintenance of basal ACTH levels, and then 3 h after ADX, to investigate CORT suppression of elevated ACTH levels induced by prior ADX. Regarding proactive feedback, the results showed that injection of CORT at the time of ADX was only partially effective in preventing ACTH elevations, whereas CORT pellets maintained basal levels of ACTH in all ADX pups. The reactive mode of negative feedback in nondeprived pups was resistant to CORT injection, whereas the CORT pellet resulted in a return to basal levels within 60 min. Maternal deprivation did not affect proactive feedback, but caused a more sustained increase in ACTH levels and a failure to return to basal levels 3 h after ADX despite significantly higher levels of circulating CORT in these DEP pups. It is concluded that 1) proactive and reactive modes of negative feedback are operative, provided the pups are maintained on chronic replacement with CORT; 2) DEP impairs the reactive, rather than the proactive, mode of feedback inhibition in the neonate.

Maternal deprivation and stress induce immediate early genes in the infant rat brain.

The hypothalamic-pituitary-adrenal (HPA) axis is normally quiescent during the stress-hyporesponsive period (SHRP) from day 4-14 in infant rats. However, maternal deprivation (DEP) can disinhibit the HPA axis, thus enabling neonatal rats to respond to mild stressors. In an effort to understand how DEP may alter HPA axis sensitivity, we used in situ hybridization to measure changes in the expression of stress-responsive genes in the brains of neonatal rats. Despite the minimal HPA axis response in nondeprived rats during the SHRP (postnatal day 12), the mild stress of a saline injection significantly increased messenger RNA levels of two immediate-early genes (IEGs), c-fos and NGFI-B, in the hypothalamic paraventricular nucleus (PVN) and in the cerebral cortex. Following 24 h of DEP, the induction of IEGs in response to stress was greatly potentiated in the PVN of P12 neonates. In contrast, DEP attenuated the effects of stress on IEG induction in rats that had matured beyond the SHRP (P20). Surprisingly, DEP decreased basal levels of CRH messenger RNA in the PVN at P12 and P20. Thus the SHRP most accurately refers to HPA axis insensitivity to stress because the brain itself readily responds to stress as evidenced by the induction of IEGs.

Alcohol use and problem drinking: prevalences in the general Rotterdam population.

Research was done on the distribution of abstinence, excessive drinking, alcohol-related problems, and problem drinking among the general population of Rotterdam, Netherlands in 1994. Prevalences are assessed among the total population and subpopulations defined by sex, age, marital status, educational level, daily activities, and income. A general population survey was conducted among a random sample of 8,000 Dutch inhabitants of Rotterdam in the 16-69 age range. The response rate was 44% (N = 3,537). The majority of the respondents were "light" or "moderate" drinkers. Prevalences of excessive drinking, alcohol-related problems (1 or more), and problem drinking in the total population were 8, 28, and 9%, respectively. It is shown that women tend to report many alcohol-use-related problems considering their relatively low consumption pattern; young men have a high prevalence of problem drinking; being single, being unemployed, and being declared unfit to work are associated with problematic drinking. The results found for socioeconomic status appear to be inconsistent.

The Dutch instant lottery: prevalence and correlates of at-risk playing.

After a long and contentious political debate, the instant lottery was introduced in the Netherlands in 1994. One of the conditions for allowing the introduction was that an evaluation study should be conducted with regard to possible negative side effects of the instant lottery in terms of excessive playing or addiction. This article reports on the main results of this evaluation study. In a random sample of 4497 instant lottery players, at-risk players were differentiated from recreative players on the basis of level of involvement in the instant lottery, impaired control and the experienced negative consequences of playing. Of the sample, 4.1% could be classified as an at-risk player. Actual problems resulting from playing in the instant lottery were experienced by 0.7% of the players. At-risk players and recreative players did not only differ substantially in their playing behaviour, but also with regard to their socio-economic background, playing motivation, participation in other games of chance, and involvement in alcohol use and use of marijuana. To summarize, at-risk players were more likely to come from a poor socio-economic background, to play the instant lottery with a negative playing motivation, to be heavily involved in other forms of gambling, to have used marijuana and to drink alcohol excessively.

Regulation of glucocorticoid and mineralocorticoid receptor mRNAs in the hippocampus of the maternally deprived infant rat.

The hypothalamic-pituitary-adrenal (HPA) axis in the developing rat has a limited response to acute challenges between days 3 and 14 of life. Several hypotheses have been proposed to explain this quiescent state. Immaturity of brain, pituitary and adrenal elements or excessive feedback inhibition are common explanations. Recently, a series of studies by Levine and co-workers has shown that prolonged maternal deprivation (24 h) results in increased basal and stress induced corticosterone (CS) levels. An increased adrenal response to ACTH along with an enhanced and sustained ACTH response have been implicated in this phenomenon. A brain structure that appears to be important for normal HPA function is the hippocampus, a structure rich in corticosteroid receptors, which has been hypothesized to play a role in the basal tone of the HPA and in the magnitude and duration of stress responses. Thus, to study further the possible mechanisms leading to an enhanced and sustained ACTH response that is seen in maternally deprived pups, we used in situ hybridization to investigate hippocampal mineralocorticoid (MR) and glucocorticoid receptor (GR) gene expression in 12 groups of animals: six groups involved 24 h maternally deprived (DEP) and non-deprived (NDEP) rat pups at three ages (6-, 9-, and 12-days-old); the other six groups included pups similarly treated, but challenged with an exposure to a mild stressor (saline injection) and sacrificed 1 h thereafter. We found: (1) an age effect for almost every hippocampal subfield for both MR and GR mRNAs: MR increases with age, while GR decreases: (2) down-regulation of MR mRNA in CA1 region in the DEP animals; and (3) down-regulation of GR mRNA, also in CA1, in the saline-injected DEP and NDEP animals. Our results indicate that corticoid receptors in the developing CA1 hippocampal region appear to be sensitive to circulating CS. They also suggest that the relative ratio of GR and MR in the CA1 region may contribute to the enhanced and sustained CS response seen after a mild stressor in deprived animals.

Qualitative health research and health promotion at the local level.

The Municipal Health Service for Rotterdam area in the Netherlands has developed a health research strategy with special focus on qualitative methods. This article describes one of the first and most instructive cases in which this strategy has been applied: a local health study in "Feijenoord." The research in Feijenoord was carried out between 1989 and 1990 making it possible to look both at the short-term and long-term effects. Quantitative data were used to describe the neighborhood health situation. Qualitative data were used to expand on this description. The qualitative information was obtained from residents and workers in health care and welfare using focused interviews and nominal group interviews. The results and effects of the research presented were influential. The research started a train of activity that could not have been predicted, and of which the Municipal Health Service had little control at first. An important effect in the short-term was that, as bringer of unpleasant news, the Municipal Health Service was unfavorably regarded. In the long-term, the Municipal Health Service participated significantly in the activities set up within the health framework. After evaluating these effects it was possible to formulate the conditions for an effective use of qualitative methods in public health research.

Activation and inhibition of the hypothalamic-pituitary-adrenal axis of the neonatal rat: effects of maternal deprivation.

These studies investigated the activation and inhibition (negative feedback) of the neonatal rat. The ACTH response of maternally deprived pups is persistently elevated for 30 min, suggesting a deficiency in the negative feedback system. In Experiment 1, we examined the time-course of corticosterone (CORT) and ACTH responses to a saline injection over a 120-min period during development. In deprived pups, CORT and ACTH were persistently elevated throughout the testing period, whereas only 15-day-old nondeprived pups showed ACTH and CORT elevations. Further nondeprived and deprived pups were exposed twice to ether (Experiment 2) or saline injections (Experiment 3) separated by a 1-h interval. Nondeprived pups showed an augmented ACTH response to double exposure to ether, but not to saline. No CORT response to either stimulus was observed. In response to one exposure of each stimulus, deprived pups showed increased ACTH and CORT values and no further elevation to repeated exposure. These results suggest the negative feedback system of neonates is immature, but partially functional in deprived pups. Moreover, nondeprived pups show a stressor-specific response to stress, whereas deprived animals show a similar response to different stimuli.

Differential influence of corticosterone and dexamethasone on schedule-induced polydipsia in adrenalectomized rats.

Previous studies have shown that adrenalectomy prevents the normal acquisition of schedule-induced polydipsia (SIP), while corticosterone (CORT) administration reinstates this behavior in adrenalectomized (ADX) rats. These studies investigated which corticosteroid receptor is responsible for mediating CORT effects on SIP. In Experiment I the effects of dexamethasone (DEX) and CORT on the acquisition of SIP were studied. DEX and CORT pellets (respectively 15 mg and 200 mg) were implanted subcutaneously in ADX rats. CORT but not DEX replacement was able to reinstate SIP in ADX rats. Because DEX binds almost exclusively to glucocorticoid receptors (GRs), while CORT binds to both GRs and mineralocorticoid receptors (MRs), results from Experiment I indicated that occupancy of GRs alone is not sufficient for SIP acquisition. In Experiment II CORT pellets of different concentrations (1, 10, 50, 200 mg) were implanted in ADX rats in order to determine whether MRs alone, or a combination of GRs and MRs are required for SIP reinstatement. Results from Experiment II showed that the 1 and 10 mg CORT pellets were not able to reinstate SIP in adrenalectomized rats, while animals implanted with 50 or 200 mg pellets did exhibit the behavior. These results indicate that occupancy of both MRs and GRs is required for SIP acquisition.

Interleukin-1 beta, but not interleukin-6, impairs spatial navigation learning.

The effects of the cytokines interleukin-1 and -6 (IL1 beta, IL6; 100 ng) on spatial learning were examined in the Morris water maze. Intracerebroventricular injection of IL1 or IL6 before the training on day 1 did not influence the acquisition of spatial navigation. However, IL1 administered at 60 min, but not immediately before the training, resulted in impaired performance of spatial navigation the following day. In contrast, IL6 administered at both times had no effect. In a second experiment the same doses of IL1 and IL6 increased the body temperature of rats in a time-related fashion. The temperature effect of IL1 developed after a delay of 120 min, while the IL-6-effect was immediate. Comparable behavioral changes might accompany infections or inflammatory diseases and therapeutic cytokine administration.

Differential effect of ACTH1-24 and alpha-MSH induced grooming in the paraventricular nucleus of the hypothalamus.

Injection of ACTH1-24 as well as alpha-MSH in the paraventricular nucleus of the hypothalamus (PVH) induces intense grooming in the rat. While comparing the details of MSH, ACTH and control grooming, we found that the induction of grooming was highly site specific. Even injection of saline in that specific area produced some grooming, possibly due to the release of endogenous substances. To distinguish between effects caused by the peptides and the effects caused by the injection procedure, we compared the behavioural effects of saline and peptide injections in sites with exactly the same location in the PVH, in a post-hoc matched pairs design. Using this design we found that the grooming response induced by saline is of a limited duration. ACTH1-24 and alpha-MSH prolong grooming beyond that period. Interestingly, rats receiving alpha-MSH continued to groom, while rats receiving ACTH1-24 changed to scratching. This confirms earlier findings suggesting that grooming and scratching have a differential organization at the level of the PVH. Whether the peptides also have a role in the initiation of the grooming response, or just prolong a response caused by other local factors requires another experimental approach.

Sensory evaluation of drinking water by consumer panels.

The human senses play an important role in assessing the quality of food and of the environment. Particularly the chemical senses of taste and smell determine the pleasantness of foods and drinks and may provide a warning mechanism for the presence of more or less toxic contaminants. Even after the recent rapid development of powerful analytical techniques the human nose can easily detect trace amounts of chemicals at levels many times lower than the analytical detection limits. Although taste and odour assessment of drinking water has been practiced in many waterworks laboratories by small panels, relatively unreliable results were obtained and such sensory data played up till now only a minor role in the management of the water treatment plant. More sophisticated and reliable methods for sensory water quality evaluation are discussed. Special attention is given to the characteristics of the human senses of taste and smell, to which the methodology of sensory assessment should be better adapted. High numbers of observations on a sample are generally needed, for which purpose the use of large panels has to be realized. In this respect the help of large consumer panels is an alternative for the presently often used small laboratory groups. As an example the preliminary results of a large ongoing experiment of sensory water quality assessment by 2 consumer panels of 100 persons each in the Rotterdam area are discussed. Drinking water quality is judged at the consumer homes every week. The experiment started September 1979 and will be continued for one year.