Research into the mouthing behaviour of children up to 5 years old. Consumer and Competition Policy Directorate 22010 DTI Mouthing rep cover 28/8/02 12:00 Page 4 22010 DTI Mouthing rep cover 28/8/02 11:59 Page 1 Research commissioned by the Consumer and Competition Policy Directorate, DTI. Department of Trade and Industry 1 Victoria Street London SW1H 0ET Carried out under contract by: Dr Beverley Norris Stuart Smith Institute for Occupational Ergonomics School of Mechanical, Materials, Manufacturing Engineering and Management University of Nottingham University Park, Nottingham, NG7 2RD Tel: 0115 9514039 Fax: 0115 9514000 July 2002 URN 02/748 22010 DTI Mouthing rep cover 28/8/02 11:59 Page 2 22010 DTI Mouthing rep cover 28/8/02 11:59 Page 3 SUMMARY 1 CHAPTER 1. Design of the research 2 1.1 Aims of this research 2 1.2 Data Collection 2 1.3 Experimental design 3 CHAPTER 2. Methodology 5 2.1 Development of materials 5 2.1.1 Pre-pilot trials 5 2.1.2 Pilot trials 5 2.2 Observation protocols 6 2.2.1 Timing of mouthing behaviours 6 2.2.2 Classifying what was mouthed 6 2.2.3 Classifying the type of mouthing behaviour 6 CHAPTER 3. Participant Details 7 3.1 Children's mouthing characteristics and child care details 7 CHAPTER 4. Results 10 4.1 Estimated daily mouthing time by item mouthed 10 4.2 Estimates of daily mouthing times according to what was mouthed and how 13 4.2.1 All items 14 4.2.2 Dummy/soother 14 4.2.3 Fingers 16 4.2.4 Toys 18 4.2.5 Other objects 20 4.2.6 Items not recorded 22 4.3 What was mouthed 23 4.3.1 Categories of toys and other objects mouthed 23 4.3.2 Mouthed toys and other objects by material 25 4.3.3 Items intended to be mouthed 26 4.3.4 Number of items mouthed 29 CHAPTER 5. Validation 30 5.1 Analysis of mouthing time 30 5.2 Analysis of what was mouthed 31 5.3 Analysis of how the children mouthed 32 Contents Page No 22010 DTI Mouthing Report 28/8/02 11:46 Page 1 CHAPTER 6. Discussion 33 6.1 Validity and reliability of the study 33 6.2 Mouthing times 33 6.2.1 Mean and maximum mouthing times 33 6.2.2 What is mouthed 34 6.2.3 How items are mouthed 34 CHAPTER 7. Implications 36 7.1 Why children mouth 36 7.2 Overview of legislation and standards 36 7.3 Accident statistics on mechanical hazards 37 7.4 Mouthing times 38 7.5 Items mouthed 38 7.6 Hazards from items mouthed in this study 39 7.7 Reducing accident levels 43 7.7.1 Toys 43 7.7.2 Other objects 44 7.8 Using product features to deter mouthing 44 CHAPTER 8. Conclusions 45 CHAPTER 9. Recommendations 47 9.1 Toys 47 9.2 Other objects 47 CHAPTER 10. References 49 Appendix A: Observation recording form 50 Appendix B: Toy and objects details sheet 51 Appendix C: Child’s daily routine form 52 Appendix D: Questionnaire 53 Appendix E: Pictures illustrating mouthing behaviours 56 Appendix F: Examples of Toy Categories 57 Appendix G: Examples of "other objects" categories 69 22010 DTI Mouthing Report 28/8/02 11:46 Page 2 Page 3 Summary This report supplements "Report on research into the mouthing behaviour of children up to 5 years old – Executive Summary" (DTI, 2002). This report presents background information to the study and further data and discussion from the study, specifically: i) Information regarding the methodology and protocols of the study ii) Background data on the sample: Details of children’s mouthing habits, the child’s family, the observers and their care and work circumstances and child care arrangements iii) Estimated data on time spent each day mouthing on dummy/soothers, fingers, toys, and other objects by how the items were mouthed, for each age group iv) Details of the validation study v) Discussion of the findings of the work vi) Details of the items mouthed in the study vii) Literature review of chemical and mechanical hazards from children’s toys and other plastic items viii) The forms used in data collection. Information presented in this report should be used in conjunction with the summary report described above. 22010 DTI Mouthing Report 28/8/02 11:46 Page 3 1.1 AIMS OF THIS RESEARCH The research described in this report was designed to expand upon the knowledge of the mouthing behaviour of children. The ages of children to be observed in this study ranged from 1 month to 5 years, to investigate the extent of exposure to products at this older age (given the findings of Warren et al. (2000) that over 20% of the children in their study carried a non-nutritive sucking habit past the age of 36 months). The overall aim of the project was to produce a figure for the total time that children within this age range are expected to mouth items per day. This could then be used to assess potential mechanical hazards posed by items on which children were found to mouth. 1.2 DATA COLLECTION The behaviour of young children may be greatly affected by all types of stimuli. In studies such as this where we are attempting to gain information on normal and natural behaviour of children it is imperative that the environment in which the data are gathered is as unaffected by the observation as possible. This means that the child should be surrounded by things that they are used to and know. For this reason, the research by Groot et al (1998) and Juberg et al (2001) both rely on data being recorded by the parent(s) of each child using a diary format. The child is obviously used to the presence of their parent and so natural behaviour may be assumed. The use of a structured formal diary recording system serves to control the type of information that the parent is recording and therefore provides a level of validity and reliability to the research. Greater levels of reliability would possibly be obtained through the use of trained researchers observing the child in their home environment, as the observer is trained to record certain types of behaviour consistently, and so providing good repeatability of observation. The same is true for the use of video recording equipment, where very short behaviours can be reliably recorded. However, it is likely that a child will be very aware of a video camera and being filmed, and this could lead to a change in behaviour. Likewise, the presence of a stranger in the home is likely to alter the behaviour of the child being observed to a greater or lesser extent, so while the reliability of the data may be high, the circumstances are less "realistic" and lower the validity of the data. Another problem with video recording is that young children are often on the move, which would make capturing every behaviour extremely difficult. For these reasons this research used parents/carers as observers, to ensure children’s mouthing behaviour, and behaviour generally, were as natural as possible to ensure high data validity. Observations were carried out at home rather than nurseries or childcare establishments as the home environment has a vast range of items that are accessible to children, not all of which are intended for use by them. This is a worst case scenario but also realistic compared to more sterile environments such as playgroups and nurseries where the contents of rooms are very carefully and rigidly controlled. Because of the factors mentioned above it was felt that an examination of the reliability of parents as observers should be carried out. This has not been investigated by prior studies which have also used parents as observers. A comparison of parent and trained observer data collection was carried out on a sample of 25 children. Information on this validation part of the research may be found in Section 5 of this report. Page 4 Chapter 1 Design of the Research 22010 DTI Mouthing Report 28/8/02 11:46 Page 4 Page 5 1.3 EXPERIMENTAL DESIGN Observation was carried out by parents in the child’s home for a total of five hours, split into 20 fifteen minute observation sessions. A period of two weeks was allowed for the observations to be completed and the data returned. These observation sessions were to be spread out over different times of the day and the week as follows: i) Weekdays: • 4 fifteen minute sessions between the child waking and 11am • 4 fifteen minute sessions between 11am and 2 pm • 4 fifteen minute sessions between 2pm and 6pm • 4 fifteen minute sessions between 6pm and the child going to bed for the night ii) Weekend: • 1 fifteen minute session between the child waking and 11am • 1 fifteen minute session between 11am and 2 pm • 1 fifteen minute session between 2pm and 6pm • 1 fifteen minute session between 6pm and the child going to bed for the night. This gives in total 5 hours of observation time on each child. Observations could be done at the discretion of the parent at any time within these zones. However, no more than two observation sessions were allowed within the same time zone on any one day, and at least 30 minutes was required to be left between observation sessions. These provisions were included in order to ensure data was gathered spread evenly across the days and week to gather a representative picture of the child’s behaviour, and also to reduce potential errors from fatigue caused by observation. In each 15 minute observation session the following information was recorded: • the duration of each mouthing behaviour • what types of items were mouthed • the type of mouthing behaviour for each item mouthed • what was mouthed • which room of the house the observation was undertaken in • other people present in the room • whether the child was feeling unusually ill or tired during the observation • how long it had been since the child last ate and slept • what the child was doing during the observation. 22010 DTI Mouthing Report 28/8/02 11:46 Page 5 Information gathered over the whole study for each participant also included: • details of the child’s physical and psychological development • details of the child’s family (e.g. size, type of house lived in, social class) • details of the time the child spent outside of the family home in a care environment (e.g. a nursery, playgroup) • details of toys mouthed by each child, part of toy mouthed and what each part mouthed was made of • details of what other objects were mouthed and what they were made of • details of the child’s daily routine for the first and last days that they were observed i.e. what time they got up and went to bed, and time spent eating and sleeping during the day. The questionnaires and forms used to gather these data are presented in Appendices A, B, C and D. Page 6 22010 DTI Mouthing Report 28/8/02 11:46 Page 6 [...]... The number of behaviours and mouthing times observed by the trained observer and the parent were very similar, with total mouthing time, mean mouthing time and maximum observed mouthing time all being exactly the same, and number of behaviours observed and standard deviation being very similar As anticipated, the video analysis captured more incidences of mouthing behaviour and thus potentially more... mouthing on toys and other objects and total mouthing on these two items.(hours: minutes: seconds) It is apparent that after the age of 6-9 months mouthing on toys and other objects generally decreases 4.2 ESTIMATES OF DAILY MOUTHING TIMES ACCORDING TO WHAT WAS MOUTHED AND HOW Mouthing time is presented for mouthing on all items and also separately for each category of item mouthed (for males and females... Fingers (and other parts of the body) 4.2.4 Toys 4.2.5 Other objects 4.2.6 Item not recorded Page 15 22010 DTI Mouthing Report 28/8/02 11:46 Page 16 4.2.1 All items Estimated daily mean mouthing time is presented in Figure 4, for mouthing on all items, by how items were mouthed at each age group 2:15:00 2:00:00 Mean mouthing time 1:45:00 lick, suck and bite suck and bite lick and bite lick and suck... mouthing behaviour at all ages 4.2.2 Dummy/Soother Figure 5 shows how dummies/soothers were mouthed at each age group, and Table 5 presents the estimated daily mouthing data shown in Figure 5 1:20:00 Mean mouthing time 1:10:00 Not recorded Lick, Suck and Bite Suck and Bite Lick and Bite Lick and Suck Bite Suck Lick 1:00:00 0:50:00 0:40:00 0:30:00 0:20:00 0:10:00 5 4 3 2 21-24 18-21 15-18 12-15 9-12 6-9 3-6... - - Mean - - - - - - - - 0:00:37 - - - Max - - - - - - - - 0:24:15 - - - Bite Lick and Suck Lick and Bite Suck and Bite Lick, Suck and Bite Mean 0:01:36 0:00:47 0:02:52 - 0:00:22 0:05:00 0:04:00 - 0:02:01 - - - Max Not recorded 0:14:28 0:05:37 0:34:14 - 0:05:22 0:45:26 0:32:25 - 0:32:00 - - - Table 5: Estimated mean and maximum daily mouthing time on dummy/soothers by how they were mouthed Page 17... 0:35:00 0:30:00 0:25:00 0:20:00 0:15:00 0:10:00 0:05:00 0:00:00 5 4 3 2 21-24 18-21 15-18 12-15 9-12 6-9 3-6 Not recorded Lick, Suck and Bite Suck and Bite Lick and Bite Lick and Suck Bite Suck Lick 1-3 Mean mouthing time Figure 6 shows how fingers were mouthed at each age group, and Table 6 presents the estimated daily mouthing data shown in Figure 6 Age category Figure 6: Estimated mean daily mouthing time... 22010 DTI Mouthing Report 28/8/02 11:47 Page 20 4.2.4 Toys Figure 7 shows how toys were mouthed at each age group, and Table 7 presents the estimated daily mouthing data shown in Figure 7 0:45:00 Mean mouthing time 0:40:00 Not recorded Lick, Suck and Bite Suck and Bite Lick and Bite Lick and Suck Bite Suck Lick 0:35:00 0:30:00 0:25:00 0:20:00 0:15:00 0:10:00 5 4 3 2 21-24 18-21 15-18 9-12 6-9 3-6 1-3... 0:00:14 0:01:20 0:00:18 0:00:17 0:00:56 0:00:04 0:00:09 0:00:15 0:00:01 0:00:01 0:00:01 Max Lick and Suck - 0:01:17 0:07:23 0:01:34 0:03:10 0:10:34 0:00:57 0:01:28 0:07:58 0:00:05 0:00:07 0:00:27 Lick and Bite Suck and Bite Lick, Suck and Bite Not recorded 0:01:12 0:00:08 0:00:18 Table 7: Estimated mean and maximum daily mouthing time on toys by how they were mouthed (hours:minutes:seconds) Page 21... Report 28/8/02 11:47 Page 22 4.2.5 Other objects Figure 8 shows how other objects were mouthed at each age group, and Table 8 presents the estimated daily mouthing data shown in Figure 8 0:30:00 Mean mouthing tim e 0:25:00 Not recorded Lick, Suck and Bite Suck and Bite Lick and Bite Lick and Suck Bite Suck Lick 0:20:00 0:15:00 0:10:00 5 4 3 2 21-24 18-21 15-18 9-12 6-9 3-6 1-3 0:00:00 12-15 0:05:00... - Mean - - - - - - - - - - - - Max - - - - - - - - - - - - Lick Suck Bite Lick and Suck Lick and Bite Suck and Bite Lick, Suck and Bite Page 24 Mean 0:00:03 0:00:16 - - 0:00:02 - - 0:14:13 0:02:40 0:00:01 - 0:02:56 Max Not recorded 0:00:23 0:03:07 - - 0:00:26 - - 2:50:37 1:35:15 0:00:37 - 1:05:08 Table 9: Estimated mean and maximum daily mouthing time on items not recorded by how the items were mouthed . 11:59 Page 1 Research commissioned by the Consumer and Competition Policy Directorate, DTI. Department of Trade and Industry 1 Victoria Street London SW1H. into the mouthing behaviour of children up to 5 years old. Consumer and Competition Policy Directorate 22010 DTI Mouthing rep cover 28/8/02 12:00 Page