DESCRIPTION OF THE SURVEY

Labo has for many years been studying consumers’ satisfaction with natural hair growth, in relation to its product Crescina Re-Growth, using a short paper-based questionnaire administered directly in pharmacies which sell the product. In total 2000 questionnaires have been administered to Crescina consumers since 2001. Labo now wanted to analyse the figures generated by these questionnaires in order to evaluate the growth performance levels achieved by Crescina over this period (from 2001 to the present).

The questionnaire was administered to Crescina Re-Growth consumers selected at random in pharmacies, subject to the condition that the selection of interviewees must result in a reliable sample and, accordingly, repeatable results. To explain: while proportions (such as gender, age, etc.) were not fixed beforehand because their distribution within the population of Crescina consumers was not known, the random finding of consumers in the pharmacy, together with the great number (2,000) of cases studied, nevertheless guarantee that the sample obtained is in keeping with the real distribution of the Crescina consumers.

For each question, as well as finding the percentage distribution of the replies we performed significance tests to check whether every element of chance in the results obtained could be ruled out (i.e. whether the replies were statistically significant); we also checked whether the effectiveness of Crescina Re-Growth had changed over time.

SIGNIFICANCE TESTS APPLIED TO THE GROWTH RESULTS

To analyse the effectiveness of Crescina Re-Growth, both on one occasion and over time, two types of significance test were used:
> type A significance test: this tests whether, for a given question, the percentages of the various replies (for instance “% Yes” vs. “% No”) were significantly different (and hence that the difference is not due to chance). This test consists of a significance analysis conducted on the total of 2,000 interviews over all three years studied (2001, 2002 and 2003);
> type B significance test: this tests whether, for a given question asked in different years, the percentages of the same reply in the various years (for instance “% Yes in 2001” vs. “% Yes in 2002”) were significantly different (and hence that the difference is not due to chance). This test consists of a significance analysis conducted on the figures for individual years (interviewee base = 423 for 2001, 552 for 2002 and 992 for 2003).
All the tests carried out used the base hypothesis (or “Null hypothesis”, H0) that the differences between the replies are due to chance (and hence not significant), and proceeded to check whether that hypothesis could be rejected (and the differences between the replies taken accordingly to be “structural”, to be imputed to the effects of Crescina Re-Growth).
Both types of test (A and B) were run at a 5% significance level, meaning that there is a very low probability (5%) of mistakenly concluding that the differences are not significant but due to chance, when in fact they are significant and “structural”, being due not to chance but to exogenous factors.

85% of those interviewed said that after using Crescina there had been results in terms of hair growth, in the areas presenting thinning.
On analysing the individual years’ findings, we find a constant improvement in Crescina’s performance in terms of growth (from 81% in 2001 to nearly 88% in 2003).

So far as the “growth” results are concerned, the following two tests were applied:
> type A test: Binomial test. The difference between the 85% figure for “Yes, there have been results in terms of growth” and that of 14.9% for “No, there have not been results in terms of growth” was found significant at the 95% confidence level;
> type B test: Z test (normal, standardised). The percentage replying “Yes, there have been results in terms of growth” in 2001 (80.9%) is lower, to a statistically significant extent, than those found in the entire sample (85.0%) and in the years 2002 (83.9%) and 2003 (87.5%). Though the difference found between the years 2002 and 2003 for the variable “growth” is NOT statistically significant, the increase recorded (from 83.9% to 87.5%) is nevertheless sufficient to show the improvement in Crescina’s performance over that period.

SUMMARY OF THE OTHER RESULTS

- More than 8 interviewees out of 10 said that after using Crescina they had noticed an increase in hair thickness. In terms of this observed variable, also, we found improvements over the period, from 77% for the two years 2001-2002 to 85% in 2003.
- Out of the 2,000 questionnaires analysed, about half had been administered in 2003, nearly 30% in 2002 and just over 20% in 2001.
- All three sub-samples analysed (for the years 2001, 2002 and 2003) gave virtually the same average age (just over 43 years), confirming that the random procedure for selection of consumers in the pharmacies did result in a sample whose distribution was in line with that of the underlying real population (Crescina users). This means that there was no bias in the samples, from 2001 to the present, though the proportions in the sample had not been fixed beforehand.
- On average the sample of Crescina consumers interviewed used the products for just over 4 months, and this mean is higher (to a statistically significant extent) in the sample interviewed in 2001 (over 5 months, on average).
- With regard to the particular Crescina product used, the figures given above refer to Crescina 300 (17% of instances) and Crescina 200 (14%). Next comes the generic heading Anti-Hair Loss, at 12%. It should be noted that early in the surveys the Crescina products were mentioned more frequently (either generically, or in the specific versions: 100, 200, 300, 500 or 700), as were the Supercrescina ones (either generically, or in its specific versions), and Shampoo/Shampoo Plus. In 2002, on the other hand, we find higher percentages than in the other years using Re-Growth, Anti-Hair Loss and Crescina Plus/Re-Growth Plus, while in 2003 there were greater proportions using Crescina Forte/Re-Growth Forte, and under the heading “Complete Care”.

OTHER RESULTS