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A Schnuch

Publications and source records attributed to A Schnuch.

66 records · Page 4Linked to original sources

PAFS: population-adjusted frequency of sensitization. (I) Influence of sex and age.

Sensitization rates are influenced by sex and age. Crude rates from different departments cannot be compared without taking into account these variables. However, the influence of sex and age has never been considered quantitatively. In 2 hypothetical populations with identical age-specific sensitizations rates, but differing age distributions, the influence of age on the overall sensitization rate (crude rate) is demonstrated. Furthermore, by an abstract reflection on rates, the influence of the proportions of a population category (e.g., age) on crude rates is shown (crude rate = sigma (category-specific rate x proportion of population in category)). To account for differing distributions of sex and age, we propose 2 ways. Sex-specific rates should be presented separately. Age-specific rates should be standardized. The standard rate is defined as: SR = sigma (category specific rate x proportion of standard population in category). Using a standard population with a rectangular structure (i.e., with equal proportions in each of the category (age) specific groups), the standardized rate is the arithmetic average of the category (age) specific rate. Only for simple routine evaluations can a standard population with 2 equal groups be used, namely over 39 years and under 40 years. The standardized rate can easily be calculated as SR: (positive rate (%under 40 + positive rate (%) over 39)/2. The general rule should be to use a "rectangular" standard population with 9 age groups of a 10-year sequence. By using the standardization procedure; remaining differences found in different departments can no longer be attributed to age and sex. Other factors, such as selection of patients or real epidemiological differences, can then be discussed. The application of population-adjusted frequency of sensitization (PAFS) in any publication on prevalences of sensitization is highly recommended.

Adolescent↗

Good clinical practice in patch testing: readings beyond day 2 are necessary: a confirmatory analysis. Members of the Information Network of Departments of Dermatology.

BACKGROUND: Despite general recommendations, patch test readings are still sometimes terminated at day 2. OBJECTIVE: The consequences of failure to read patch tests after day 2 and the influence of exposure time to the patches is quantified. METHODS: Patch test data from 9,946 patients with at least one positive reaction at day 2 or later and readings at both days 2 and 3 (from 21,062 patients tested between January 1, 1990, and December 31, 1993) collected by the Information Network of Departments of Dermatology in Germany were analyzed. RESULTS: Comparing results at days 2 and 3, 34.5% of all positive reactions appeared at day 3 only, whereas 8.3% initially judged (weakly) positive were not considered allergic at day 3. Some standard allergens showed specific patterns. Additional positive reactions and an increasing percentage of diminishing reactions can be observed at day 4 (compared with day 3). CONCLUSION: The importance of late reading(s) is emphasized by the proportion of potentially false judgments based on readings at day 2 only.

Allergens↗

Epidemiology of contact dermatitis. The information network of departments of dermatology (IVDK) in Germany.

In 1988, the multicenter project "Information Network of Departments of Dermatology (IVDK)", including eight university skin hospitals was founded. It now comprises 30 participating centers. At these centers, all patch test results are recorded, together with important anamnestic details and, twice a year, these are sent to the data center at the Göttingen University Skin Hospital. Regular, descriptive analyses of data collected by this epidemiological surveillance system serve the different purposes discussed in this paper: 1) observation of "sentinel events"; e.g. an increase in the proportion of patients tested who were sensitized to a certain allergen, or the identification of certain subgroups at particular risk as a starting point for further research or preventive action, and 2) advancement of good clinical practice in patch testing. In October 1996, a working group of the European Society of Contact Dermatitis (ESCD) called the "European Surveillance System on Contact Allergies (ESSCA)" was established with a similar aim of communal data collection and analysis.

Dermatitis, Contact↗