All parents of patients who were in-patients or attending outpatient clinics of our department, a private paediatric clinic, as well as the nursing and secretarial staff of this hospital were recruited for the study. Parents were approached individually by one of the authors (FYK) and the purpose of the survey was explained. A semi-structured interview based on the questionnaire (see Additional file 1) was conducted in Cantonese. Exclusion criteria include non-Chinese speakers and absence of parents.
The current study did not involve any medical intervention nor invasive intervention to the subjects and no ethical approval was deemed necessary under Hong Kong ethical framework.
"Hot Qi" questionnaire
Parents were asked to express their view on the term "Hot Qi" as used on their children, one child per parent, based on a questionnaire (appendix 1). This questionnaire was developed by DKN and DC (a registered TCM practitioner). "Hot Qi" was investigated with the question: "Have you ever used the term "Hot Qi" to describe your child?" Parents who answered "yes" were asked to volunteer symptoms of "Hot Qi" that their children displayed and the remedies used.
All analysis was done with statistical software (Statistical Package for the Social Science, release 11.0.4 for Macintosh; SPSS; Chicago, IL). All continuous data were presented as mean and standard deviation. Age of children was compared between those who used the term "Hot Qi" and those who did not by Mann-Whitney U test. The categorical variables, included age group of parents, gender of parents, education level of parents, place of birth of parents, household income, gender of children were compared by Chi-squared test. Variables with significant difference between the two groups of parents were entered into a forward logistic regression model to predict the use of "Hot Qi" in parents. The demographical predictors of "Hot Qi" with adjusted odds ratio significantly larger than one were reported. Top five symptoms of "Hot Qi" and Top five remedies of "Hot Qi" were reported.
In those who reported use of the term "Hot Qi", we compared the mean age of children between those used and those who did not use a specific remedy by unpaired t-test. "Consumption of herbal products" was defined as any positive answer for "Five-flower-tea" (a combination of several flowers such as Chrysanthemum morifolii, Lonicera japonica, Bombax malabaricum, Sophora japonica, and Plumeria rubra), "selfheal fruit spike" (Prunella vulgaris), appetite stimulant (A brew from malt, juncus, and bomboo leaves), Abrus herb (Abrus precatorius), Turtle Jelly, Mulberry leaf & Chrysanthemum flower tea, Bo Ying Compound (a generic TCM product with the ingredients: Moschus, Calculus Bovis, Borneolum syntheticum, Margarita, Lapis micae aureus, Alumen, Succinum, Herba ephedrae, Arisaema cum bile, Concretio silicea bambusae, Rhizoma paridis, Radix saposhnikoviae, Rhizoma pinelliae, Bulbus Fritillariae cirrhosae, Scorpion, Rhizoma coptidis, Bombyx batryticatus, Ramulus uncariae cum Uncis, Radix curcumae, Herba menthae, Rhizoma gastrodiae, Periostracum cicadae), 24 taste herb tea, instant chrysanthemum tea and "Yin Chiao Chieh Tu Pien" (a generic TCM product with the ingredients: honeysuckle flower, forsythia fruit, platycodon root, peppermint, bamboo leaf, licorice root, schizonepeta, burdock root and black soybean). All significance tests were two sided, and a p < 0.05 was considered statistically significant.