Comparison between two common methods for reporting cold and diarrhoea symptoms of children in daycare centre research

Duration of symptoms of respiratory tract infections in children: systematic review

OBJECTIVE

To determine the expected duration of symptoms of common respiratory tract infections in children in primary and emergency care.

DESIGN

Systematic review of existing literature to determine durations of symptoms of earache, sore throat, cough (including acute cough, bronchiolitis, and croup), and common cold in children.

DATA SOURCES

PubMed, DARE, and CINAHL (all to July 2012).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials or observational studies of children with acute respiratory tract infections in primary care or emergency settings in high income countries who received either a control treatment or a placebo or over-the-counter treatment. Study quality was assessed with the Cochrane risk of bias framework for randomised controlled trials, and the critical appraisal skills programme framework for observational studies.

MAIN OUTCOME MEASURES

Individual study data and, when possible, pooled daily mean proportions and 95% confidence intervals for symptom duration. Symptom duration (in days) at which each symptom had resolved in 50% and 90% of children.

RESULTS

Of 22,182 identified references, 23 trials and 25 observational studies met inclusion criteria. Study populations varied in age and duration of symptoms before study onset. In 90% of children, earache was resolved by seven to eight days, sore throat between two and seven days, croup by two days, bronchiolitis by 21 days, acute cough by 25 days, common cold by 15 days, and non-specific respiratory tract infections symptoms by 16 days.

CONCLUSIONS

The durations of earache and common colds are considerably longer than current guidance given to parents in the United Kingdom and the United States; for other symptoms such as sore throat, acute cough, bronchiolitis, and croup the current guidance is consistent with our findings. Updating current guidelines with new evidence will help support parents and clinicians in evidence based decision making for children with respiratory tract infections.

Diarrhea and colds in child day care centers: impact of various numerator and denominator definitions of illness episodes

BACKGROUND

Numerators and denominators used to estimate infections' incidence rates (IRs), incidence rate ratios (IRRs), and differences (IRDs) vary. Our objective is to quantify the impact of various common definitions for illness episodes (numerators) and person-time at risk (denominators) in estimating these measures.

METHODS

Data were from a cohort study in which daily occurrence of illness and children's attendance in day care centers were recorded. We compared 4 IR estimates using various definitions of episode and at-risk time units.

RESULTS

IRs for diarrhea and colds were highest using child-days, lowest for diarrhea using child-weeks, and lowest for colds using child-months. The 4 methods led to similar IRRs but considerably different IRDs.

CONCLUSION

Incidence rate differences and ratios for infectious diseases can vary by the definition of episode and person-time at risk. This limits the value of the evidence base on which public health recommendations are formulated. Development of a more standard approach to measurement and reporting of IRs is recommended.

Use of diagnostic algorithms and new technologies to study the incidence and prevalence of viral upper respiratory tract infections and their complications in high risk populations

PURPOSE OF REVIEW

Most studies on the natural history of viral upper respiratory tract infections and their complications rely for ascertainment on self-assessed cold/flu illness or the identification of presumed complications. The criteria for cold/flu definition, however, are variable within and between individuals and illness is not prerequisite for a viral upper respiratory tract infection. These factors bias estimates of the incidence and prevalence of viral upper respiratory tract infections and their complications. Here we review new methodologies that can be adapted for use in future studies to refine those estimates.

RECENT FINDINGS

We present a theoretical basis for standardized assignment of cold/flu episodes using a minimal algorithm template that operates on a structured set of symptoms/signs. We emphasize the greater accuracy of information derived from longitudinal studies that incorporate identification algorithms and assay of nasal secretions for causal virus by polymerase chain reaction and for proinflammatory chemicals to confirm nasal inflammation.

SUMMARY

The methodologies and sampling strategies that we describe hold promise for better characterizing the incidence of complications for symptomatic and asymptomatic expressions of a viral upper respiratory tract infection caused by specific viruses. These data can then be used to estimate the efficacy and efficiency in a specified target population of prophylactic or intercurrent treatments to prevent the complications.

Absence from childcare for respiratory illness

BACKGROUND

This population-based study investigated prospectively collected absence for respiratory illness data in two types of formal childcare (centre day care and family day care) in Perth, Western Australia, and factors associated with such absence.

METHODS

All centres (n = 11) and 95% of family day care caregivers (n = 130) selected at random from licensing lists agreed to participate. Demographic details were obtained from a parental questionnaire and absences were recorded prospectively. Characteristics of the child and family were described using univariate odds ratios (OR) with 95% confidence intervals (CI). Multivariable analysis including generalized estimating equations was used to investigate having at least one absence for respiratory illness, having two or more absences, and having six or more absences.

RESULTS

No statistically significant difference between care types for having had at least one absence episode for respiratory illness (OR 1.37, 95% CI 0.92-2.04) was found. Children who attended care for more days per week (OR 1.40, 95% CI 1.26-1.56) and those in the study for more weeks (OR 1.03, 95% CI 1.01-1.05) were more likely to be absent for respiratory illness. Those children in care for a greater number of hours per day were less likely to be absent (OR 0.88, 95% CI 0.80-0.97). Family history of bronchitis was also associated with absence for respiratory illness (OR 1.86, 95% CI 1.32-2.63).

CONCLUSIONS

Statistically significant factors which had an impact on absence for respiratory illness were primarily those relating to the time spent in childcare and to family history of bronchitis.