(1) Do you know what causes diphtheria?

Interviewers were told that in introducing themselves to informants, and in explaining the purpose of the inquiry to them, they should be careful not to suggest by the words they used that diphtheria was an infectious disease, and should talk about children “having” or “getting” diphtheria rather than “catching” it. This was the first question asked.

If informants answered “germs” investigators asked them where the germs came from or how they were spread before classifying the answer, as the informants might think that the germs came from drains or dustbins or some such source and not from other people.

Only a quarter of the mothers interviewed gave the correct reply and a half said that they did not know. It was reported by some investigators that a few mothers experienced difficulty over the word “cause”, and it may be that the proportion of mothers knowing that diphtheria is infectious is somewhat higher than the answers to the question suggest.

Analysis by Type of District

It is of interest that a higher proportion of mothers in large towns then in small towns and country districts thought that diphtheria was caused by drains or dirt. More of those living in small towns and rural areas knew that children caught it from one another. Almost the same proportion in each type of area said they did not know the cause.

Analysis by Region

In London a relatively low proportion knew that diphtheria was an infectious disease, and in the Midlands a higher proportion than elsewhere said they did not know. Mothers in the North of England appear to be slightly better informed on this point than do those in other regions, although, as was shown in Section II, fewer children were immunised in the North than elsewhere.

Analysis by Education

As might perhaps be expected those with some higher education were considerably better informed than those with only elementary education. However, as many as 18% of the more highly educated thought that diphtheria was caused by bad sanitation or dirt.

Analysis by Economic Group

A greater proportion of mothers in the higher than in the middle and lower economic groups knew how diphtheria was spread. The difference is no doubt associated with the difference between education groups shown above, more of the mothers in the higher economic group having higher education.

Other Analyses

No statistically significant differences were found in the proportions of mothers with and without children aged over five who gave different replies.

Analysis by age of mother does not reveal any marked difference. A slightly higher proportion of those aged under thirty said they did not know and rather more of the older mothers gave positive replies of one sort or another. The proportions answering correctly are about the same in different age groups.

Analysis by whether or not Children were immunised

Division was made between mothers who had had one or more of their children aged one or over immunised, and mothers who had not had any of their children aged one or over immunised. Mothers who had only a child less than a year old (111 in all) were excluded from this analysis.

Mothers of children who had been immunised were somewhat better informed. Whether the children were immunised because the mothers were better informed or whether the mothers were better informed because some of them had learnt the cause of the disease when their children were being immunised, cannot be said.

It seems fairly clear from these results that mothers’ knowledge of the cause of diphtheria is not an important factor in determining whether or not children are immunised. Amongst the different groups for which analyses have been shown there is no positive correlation between the proportion of mothers knowing the cause, and the proportion of children immunised. It is true that both these proportions are high in the case of the higher economic and education groups, but it might be expected that these groups would be better informed in general, and not only in relation to diphtheria, than are other groups.

(2) Do you know how diphtheria can be prevented?

Interviewers were of course careful not to mention immunisation before asking this question. The question was asked immediately after the first question dealing with the cause.

Although the cause of diphtheria was known only to a small proportion of mothers the majority knew about immunisation, knowledge which from a practical point of view is certainly more important.

15% of mothers said they did not know how diphtheria could be prevented, but rather more than a third of these had actually had a child immunised. This appears to be contradictory at first sight, but considering the conditions of the interview it is not surprising. It is probable that some mothers would not remember about their children being immunised until they were specially asked about it later in the interview. Immunisation may have been carried out at school, and if the mother had signed the form without taking any particular interest in it, looking upon it as a piece of school routine, she might well forget about it until immunisation was mentioned by the interviewer. Mothers to whom this applies form 5% of the whole sample, and adding these to the 78%, mentioning immunisation spontaneously, it may be said that at any rate about 83% of mothers are aware to some extent of the possibility of preventing diphtheria. It is also of course possible that some of those who said they did not know, and who had not had their children immunised, may have heard about immunisation although it did not come to their minds when asked the open question.

The question assumed that it is possible to prevent diphtheria, but nevertheless the answer “not possible to prevent it” was given by a few mothers. Whether these mothers were entirely sceptical about immunisation, or whether they meant that immunisation (if they knew about it) is not a certain way of preventing diphtheria is not known.

Analysis by Type of District

Immunisation is mentioned more frequently by mothers living in small towns 83% and in the country 81% than by mothers in large towns 72%. The difference is not very great but it is interesting that in the case of both this question and the question about the cause, mothers living in large towns are shown to be rather less well informed than others. The proportion of children in large towns who had been immunised was however about average.

Analysis by Region

The proportion mentioning immunisation is lower in London than elsewhere and the proportion saying “Don’t know” is higher in London and slightly higher in the South than in the North and the Midlands. It will be remembered that the proportion knowing how diphtheria was spread, was lower in London than in other regions. Although mothers in London seem to be less well informed on these two points than those in other parts of the country, the proportion of children immunised is not lower in London than elsewhere.

The proportions of mothers in the North who gave correct answers to these two questions are by no means low, and yet the North had a considerably lower proportion of children immunised than other regions.

Analyses by Education and Economic Group

As might perhaps be expected greater proportions of mothers in the higher than in the lower groups knew about immunisation.

Immunisation was mentioned by 87% of those with some higher education as compared with 76% of those with elementary education only. The proportions mentioning it in the higher, middle and lower economic groups were 84% 78% and 75% respectively.

Analysis by whether or not Children were Immunised

As in the analysis of the previous question mothers who had only children aged under one were excluded.

It was pointed out previously that some of the mothers who had had children immunised did not mention immunisation in answer to this question probably because they had forgotten about it until the interviewer reminded them in a later question.

As would be expected the difference between the two groups is marked. 9% of those who had not had any children immunised said that it was not possible to prevent diphtheria. This suggests that there is a certain amount of scepticism in this group, but the proportion is small compared with the 30 answering “Don’t know”. Reasons for not having children immunised are dealt with in a later section.

(3) Do you know up to what age children should be immunised? and Do you know what is the best age to have children immunised?

“Up to fifteen” or “Until they leave school” were counted as correct answer to the first question, and “One year old” or “Just before the first birthday” were taken as correct answer to the second question.

The proportions giving different replies to the two questions were as follows.

Rather more than half know that the best age for immunisation is one or just under one, but only about a third know that all children up to fifteen should be immunised.

In the tables below only the proportions giving correct answers are shown.

Analysis by Type of District

A higher proportion of mothers living in small towns and rural areas than of mothers in large towns, knew the best age to have children immunised. A slightly higher proportion of the latter knew up to what age children should be immunised.

With both questions the proportions giving wrong answers were higher in the towns than in the rural areas, being for the first question 31%, 26% and 21% in large towns, small towns and, rural areas respectively, and for the second question 32%, 18% and 13%. Mothers in rural areas more frequently said that they did not know.

Analysis by Region

A rather higher proportion of mothers in London than of those in other regions knew up to what age children should be immunised. On the other hand more mothers knew the best age for immunisation in the Midlands and the South and East than in London and the North.

Analysis by Education

A higher proportion of mothers with higher education knew the right answer in the case of both questions.

Analysis by Economic Group

Mothers in the higher economic group were better informed on both points than those in the middle and lower groups.

Analysis by Age

A markedly low proportion of mothers in the oldest group knew the best age to have children immunised, but fewer of those in the youngest group knew up to what age immunization should be carried out. There is no very obvious reason for these differences. it is possible perhaps that mothers tended to note the points made in publicity which applied particularly to themselves or rather to their own children. More of the younger mothers would have children aged about one, that is at the best age to be immunised, and more of the older mothers would have children of school age, and would therefore be likely to know that all children up to fifteen should be immunised. An analysis made of the answers given by mothers with and without children older than five, supports this explanation.

Analysis by those with and without children aged over five

Some of the mothers in the second group (those with children over five) would of course have children under five as well.

Summary

It is clear that mothers in the higher economic groups and those with higher education are in general better informed about diphtheria than are others. This is the result that might be expected. Also children of mothers in these groups are more frequently immunised than the children of mothers in the lower economic and education groups.

It is not possible to say that mothers in particular regions are better informed in general, than those in other regions. Some points seem to have been noted more in some places and others in other places. This would of course depend largely on the relative emphasis placed on the different points in publicity in different areas.

The relatively low proportion of children immunised in the North of England is certainly not due to lack of knowledge on the part of mothers in this region, mothers in the North being as well informed on all the points studied, as mothers in the country as a whole.