Prescriptions

All together, 421 different medicines were prescribed, but in different frequencies. The 10 most prescribed medicines were responsible for 38% of the successful prescriptions; the 20 most prescribed medicines rendered 53% of the successes. The mean success rate of all prescriptions was 51%. There was no clear difference in success rate between frequently and seldom prescribed medicines. Table 4 shows the most prescribed medicines, their frequency and their success rate.

Table 4: 20 most prescribed medicines and success percentage

LR values

Calculating LR rendered 48 significant values for LR+ regarding six symptoms. Table 5 shows the results for the symptom ‘Fear of death’.

Table 5: significant LR values for the symptom ‘Fear of death’

There are some medicines where we could not calculate LR for ‘Fear of death’ because no patient had fear of death. With sufficient numbers we can state that it is unlikely that the entries of these medicines in the existing repertory-rubric are correct. We can calculate the chance that LR>1.5, for some medicines this is way below p=0.40. These medicines are Calcarea phosphorica, Medorrhinum, Mercurius and Staphisagria (see table 6).

Table 6: medicines probably not indicated by the symptom ‘Fear of death’

What does statistical variance mean for the repertory?

Table 7 shows some results of our research concerning the symptom ‘Fear of death’ as we did formerly using absolute occurrence of symptoms.

Table 7: the absolute occurrence of the symptom ‘Fear of death’ in patients with good results by various medicines.

According to this table 4 patients with good results on Aconitum had fear of death, a confirmation of the repertory-rubric. All medicines in this table, except Silicea and Magnesia carbonica, are mentioned in the repertory rubric. There seems to be very little difference between the distinctive medicines; Natrium muriaticum seems as much indicated as Aconitum if the patient has a fear of death. Probably many experienced homeopaths will doubt this outcome; experience tells us that fear of death is less related to Natrium muriaticum than to Aconitum. Now let’s look at table 8.

In table 8 we compare the occurrence of the symptom ‘fear of death’ with the total number of patients cured by that medicine, this is the prevalence of this symptom in the respective populations. Now we see much more difference and the results agree more with our experience: The prevalence of fear of death in the population cured by Natrium muriaticum is only 2%, and 40% in the ‘Aconitum population’. If Natrium muriaticum would have been prescribed only ten times, we probably would have seen no natrium muriaticum patients with fear of death.

The graphical representation of table 8 (figure 2) shows the difference more clearly. Considering the graph we would prefer Aconitum over Natrium muriaticum; we would even prefer Silicea over Natrium muriaticum if the patient has a fear of death.

A number of questions come up considering figure 2, like: why should we consider Silicea more than Natrium muriaticum while Natrium muriaticum is in the repertory-rubric and Silicea is not? One could say that the repertory has proven itself over a century, but we all know that there are many mistakes in it. It appears now that there are even systematic failures. So far the entries in the repertory were based on absolute occurrence of symptoms; if the symptom is seen in a case that responded well to the medicine, that medicine is added. We were simply not able to produce the relative occurrence (prevalence) of symptoms because we didn’t record all cases and all symptoms. Our example shows that we should use prevalence and not absolute occurrence.

Table 8: the prevalence of the symptom ‘Fear of death’ in patients that had good results from various medicines.

A new repertory

We have seen that it is better to use prevalence than absolute occurrence of symptoms. But when should we enter the medicine into the rubric? Intuitively we say “When the prevalence is more than average”, or “When the prevalence is more than in the average of the remainder of the population”. The last expression comes closest to the question if we should prefer a certain medicine over the average other medicine.

An example for the symptom ‘fear of death’, coming from our research:

Prevalence in ‘Aconitum-population’= 4/10; remainder of the population= 154/4084

The ratio between these two prevalences=10.6

Prevalence in ‘Natrium-m-population’=3/156; remainder of the population= 155/3938

The ratio between the two prevalences=0.49

So: Aconitum should be prefered over other medicines, and Natrium muriaticum should not be preferred over other medicines in a case with fear of death.

To show the difference between the old repertory, suppose that you consider to prescribe Natrium muriaticum for a patient with a certainty of 50% and then it appears that the patient has a considerable fear of death.

Old repertory: Natrium muriaticum is in the rubric, so your expected chance that this remedy will work increases (from 50% to 60%?).

New repertory: LR for Natrium muriaticum = 0.49, so your expected chance decreases from 50% to 33%.

Conclusion

Three years of research rendered 121 relevant results: 48 significant values for LR, 73 other values with sufficient probability to validate repertory-entries. Our results differ in 75% of 99 medicine-entries regarding 5 rubrics (excluding ‘sensitive to injustice’) in the original repertory, but if we disregard upgrading or downgrading of entries 56% of the medicines are unjustly entered in these 5 repertory-rubrics or missing from it. For these 5 rubrics 21 results suggest removal and 34 adding of medicines. Most additions are to the smaller rubrics, most removals are from the larger rubrics. These figures represent only 5 symptom-rubrics. We need to assess much more symptoms before we can make a statement about the correctness of the existing repertory.

Our results confirm that the reliability of the repertory can be improved. The application of a sound statistical theory like Bayes’ provides clear criteria, but also increases the scientific basis of homeopathy. However, we must still realise that the repertory is just an instrument like a weather forecast. You like it to be correct but many other variables and intuition will influence which medicine you prescribe.

The doctors participating in this research were Rob Barthels, Hetty Buitelaar, Paul Fruijtier, Gerard Jansen, Jean Pierre Jansen, Stan Jesmiatka, Christien Klein, Roland Lugten, René van der Reijden, Lex Rutten, Erik Stolper, Janny Verhey and Mechtild Wijdeveld.

For further reference read:

Stolper CF, Rutten ALB, Lugten RFG, Barthels RJWMM. Improving homeopathic prescribing by applying epidemiological techniques: the role of likelihood ratio. Homeopathy 2002;91:230-238

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. Is assessment of likelihood ratio of homeopathic symptoms possible? A pilot study. Homeopathy. 2003;92:213-216.

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. Assessing likelihood ratio of clinical symptoms: handling vagueness. Homeopathy. 2003;92:182-186.

Rutten ALB, Stolper CF, Lugten RF, Barthels RJ. ‘Cure’ as the gold standard for likelihood ratio assessment: theoretical considerations. Homeopathy 2004;93:78-83

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. Repertory and likelihood ratio: time for structural changes. Homeopathy. 2004;93:120-124.

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. Repertory and the symptom loquacity: some results from a pilot-study. Homeopathy. 2004;93:.190-192

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. A Bayesian perspective on the reliability of homeopathic repertories. Homeopathy. 2006;95:88-93

Rutten ALB. Bayesian homeopathy: talking normal again. Homeopathy. 2007;96:120-124

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. New repertory, new considerations. Homeopathy 2008;97:16-21

Rutten ALB. How can we change beliefs? A Bayesian perspective. Homeopathy 2008;97:214-219

Rutten ALB., Stolper CF, Lugten RF, Barthels RJ. Statistical analysis of six repertory-rubrics after prospective assessment applying Bayes’ theorem. Homeopathy 2009;98:26-34.

Rutten ALB. Improving homeopathic practice using Bayes’ theorem and likelihood ratio. J Altern Med Res 2009;1(1):

Wassenhoven M van. Towards an evidence-based repertory: clinical evaluation of Veratrum album. Homeopathy 2004;93:71-77