I had added 19 propositions ('stellingen') to the thesis. One of them had to be humorous in nature. I had two. Statement 17 read: 'The ''one moment please'' of telephone operators suggests that they use a different time calculation than the official one'. Statement 19 was my favorite: 'Partner swapping is not uncommon among bridge players'. This had been suggested by my father, an avid and gifted bridge player. I inherited a slightly vulgar sense of humor from him.

I can't remember if any questions were asked about the propositions (I'm afraid I am not sure what the correct translation is for 'Stellingen' with a thesis: Statements? Propositions? Postulates?). Let's see whether the Stellingen, which were not derived from my research and thesis, are still current, have become obsolete or if they have come true.

3. In order to avoid unnecessary fear among users, the information on possible side effects, stated on the package leaflet of medicines, should be presented in a more nuanced manner.

Comment: Nowadays, the frequency of side effects is expressed in percentages.

4. The idea that new contact substances must be introduced for 'allergy' to be able to develop, appears widespread, not only among laymen, but also among general practitioners.

Comment: I dare not say, but I am convinced that it is always enquired whether the patient has started using 'something new'.

5. It is urgently necessary that the indication of all components of cosmetics on the packaging (ingredient labeling) is legally required in the EEC (European Economic Community).

Comment: This wish has come true. Since 1997, all cosmetic products in the European Union must list the ingredients. My thesis research was at the basis of this and later I played an important part in getting legislation passed as Convenor of the Working Party European Community Affairs of the European Society of Contact Dermatitis.

6. Topically applied minoxidil rarely results in a cosmetically acceptable degree of new hair growth in male patients with androgenetic alopecia (male pattern alopecia).

Comment: Still absolutely correct. It is now generally accepted that its use inhibits hair loss, but that once treatment is discontinued, hair loss continues unabated.

7 The consistent rejection of ointments containing corticosteroids by some 'conscious' (aware) mothers is detrimental to their children with severe atopic eczema.

Comment: No doubt there will still be a lot of anxiety in some mothers. The fact was, is and remains that corticosteroids are fantastic for atopic (= constitutional) eczema and that, when applied correctly, the risk of serious side effects is virtually zero. I had little trouble with it myself, with those 'conscious' mothers (or would they be called 'woke' today?). Good explanation, in combination with appearing sure of yourself and with authority, works wonders. Only one mother maintained her position, if I remember correctly.

8. The Medicines Evaluation Board should have more legal powers to refuse registration of new medicines

Comment: I believe that's still the same, all drugs that work better than placebo and that have an acceptable side effect profile are allowed. Fortunately, the medical profession is becoming increasingly critical of the effectiveness (or lack thereof) of new drugs. This is especially true for the very expensive anti-cancer drugs, which result in a very limited extra survival time.

9. Methyl(chloro)isothiazolinone (Kathon CG) 100 ppm in water should be added to the European standard series of common contact allergens (A.C. de Groot and J.D. Bos. Brit J Derm 1987;116:289).

Comment: Not long after, Kathon CG (methylchloroisothiazolinone and methylisothiazolinone) was indeed added to the European Standard Series and the North American Contact Dermatitis Group screening series and is still part of them.

10. Labels on cosmetics such as 'purely botanical', 'without chemical additions', and 'inhibits wrinkle formation' indicate that the policy of the Dutch government with regard to Article 6.2 of the EEC cosmetics legislation is not having the desired effect.

Comment. It was then and it is now forbidden to make false claims on cosmetics. The cosmetic industry is now more cautious about claims that cannot be fulfilled. Nevertheless, I could submit various complaints to the advertising code committee and in a number of cases I would undoubtedly be proven right.

11. The diagnosis of 'compound allergy' often hides inadequate diagnostics.

Comment. Too complicated to explain here, but this statement remains relevant and correct.

12. Data on side effects of cosmetics, which are reported to the Keuringdienst van Waren by doctors and consumers, are of no epidemiological value.

Comment. . Still absolutely correct. For this reason, the value of the results of the CESES project, of which I was a 'supervising dermatologist' for about 6 years, is very limited. Since the payment was royal and I am no holier than the pope, I could not say no.

13. Now that it has been showns that irritation is the most common side effect of cosmetics, the introduction of 'hypo-irritative' products can be expected soon.

Comment. Nice try, De Groot, but that didn't work out. However, 'for sensitive skin' is very often used, which suggests that it will not irritate.

14. Dermatological studies on side effects of cosmetics should be used by the cosmetic industry to optimize product safety and not be seen as an attack on their industry.

Comment. At the time, dermatologists like me who investigated side effects of cosmetics, were considered hostile to the industry. While some manufacturers are still uncooperative (for example by refusing to provide patch testing materials, when an allergic reaction is reported to one of their products), hostility has largely ceased to exist.

15.Using parabens in cosmetics is relatively safe.

Comment. Yes, still. Despite this, the slogan 'Does not contain parabens' is often used in advertisements.

17. The 'one moment please' of telephone operators suggests that they use a different time calculation than the usual one.

Comment. Well, that was once, telephone operators. Nowadays you hear a recorded voice, a menu of options 'to better serve you', after entering the choice horrible music and every 20 seconds 'all our employees are still busy'. It has only gotten worse, at least at a large number of companies.

18. There is a lack of broad social support for further cuts in health care.

Comment. There are no cuts in health care these days. The budget is automatically increased by 3 billion euros every year. It's clear that it will get stuck at some point. One of the major problems is that more and more expensive anti-cancer drugs are becoming available and used. However, most of these do not cure cancer, but allow the patient to live a few months longer – often in poor health – at a huge cost, which cannot be spent on other patients.

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