A comparison of the answers from the general question and the questions in which sounds were specified by name .

Reference to the schedule of questions will show that the inquiry was introduced by a series of open questions that asked “Were there any sounds that were heard, did they trouble and did they disturb the sleep of the hearer”? In none of these questions was any specific sound mentioned.

It will be useful to refer to two types of sound - sounds from outside and sounds from neighbours. A comparison between the answers to the general question and to the specific question show that the order of sounds according to the frequency of their mention is broadly the same in both cases, but that as a rule very many more people said they heard sounds in response to a direct question mentioning it by name than mentioned them in response to the open question; thus the conclusion to be drawn from either set of questions about the relative importance of different sounds would be broadly the same. However it is clear that if the results of the general question had been relied upon the incidence of sounds would have been underestimated.

If the sounds in both lists in table 17 are compared it will be seen that for such sounds as ‘Road traffic’, the ‘Noise of children’ and the 'Wireless ‘, which are mentioned by large numbers of people, the proportions are more nearly equal than are the proportions shown for sounds mentioned by only a few people, like ‘Animals’, ‘Delivery vans’, etc. It appears, therefore, that the loss is least in the case of the sounds which are the greatest nuisance.

The difference between the two groups of answers seems to depend to some extent on the continuity or discontinuity of the sound concerned; thus ‘Wireless’ heads the list in both cases where sound from neighbours is being discussed, whereas ‘Doors banging’ is third in importance in the prompted list, but fifth in importance in the unprompted list and in several cases occasional sounds like those of ‘Delivery vans’, ‘Poultry’, ‘Lawn mowers’ are not mentioned at all in response to the unprompted questions. It appears, therefore, that the open question loses sounds which are occasional or discontinuous and are easily forgotten. That this is an important defect of the question is shown in relation to ‘Doors banging’ where this is the main source of trouble and disturbance of sleep.

The situation is illustrated in the table of comparisons below:-

SAMPLE: 2,017

+ Not Included In prompt list.