Estimated prevalence of electronic training device use
The proportion of owners reporting use of electronic training aids is fairly low compared to other training methods, although extrapolation across the estimated UK dog population of 10 million  would suggest approximately 560,000 dogs trained with these devices. Should welfare implications arise from their use, therefore, the number of animals affected is considerable. However, some caution should be used in extrapolating these data across the UK. Data from Wales was removed due to the ban implemented in Wales  making these cases unlikely to remain relevant, and those from Scotland removed due to low numbers not supporting extrapolation. There were also some (non-significant at P < 0.2) differences between regions with respect to proportion of owners using e-collars. For example, a higher proportion in the East (7.3% cases) and North East of England (6.3% of cases) was found compared to London (1.7% cases), East Midlands (2.4% cases) and the South West (2.5%) cases. Since questionnaire distribution was not even across all regions it is possible that the overall estimate of prevalence may be affected by regional differences in use. Since a higher proportion of questionnaires were distributed in the South West where reported e-collar use was lower, regional effects may mean that the figure here is an under-estimate of overall UK use of devices.
Although questionnaires were distributed in as wide a range of environments as possible, this is not a random sample, and likely to have sampling biases which are difficult to quantify. For example, it is possible that the types of owners choosing to use electronic training devices may be more or less likely to be represented in the populations sampled, or may be more or less likely to complete and return questionnaires. These figures of e-collar use should therefore be regarded as an estimate, although they are analogous with figures published by the Electronic Collar Manufacturers Association who estimate 500,000 collar owners in the UK .
Risk factors for use of remote activated e-collars
It is interesting that male owners were more likely than females to use e-collars compared to reward based methods for training their dog for recall or chasing problems. This may relate to gender differences in willingness to admit to e-collar use, or attitudinal differences to training techniques selected. Bennett and Rohlf  found that male owners were more likely to report that their dogs were ‘disobedient’ than females and so the increased use of e-collars reported by males in this study may reflect differences in attitudes towards potentially problematic behaviour. It is also possible that dogs show behavioural differences with owners of different genders .
In this study, reward based methods were more likely to be used by owners who had not attended agility classes. This may reflect preferences for training method use amongst proponents of this activity. However, further research is needed to investigate causality in this relationship, as it may reflect an attempt to resolve behavioural issues by increasing the dogs structured activities/mental stimulation/exercise by owners who also select to use e-collars.
Although there is no consensus in the literature regarding the influence of attendance at formal training classes on undesirable behaviour, a number of studies have suggested a reduction in problematic behaviour following attendance at obedience classes [27–30] and it seems inevitable that attendance at training classes, recommendations by trainers and observation of training methods used are likely to influence the subsequent selection of training methods by owners. It is therefore important that those running training classes have knowledge of the appropriate use of different training techniques and an understanding of the possible implications of their use.
Both Christiansen et al.  and Hansen et al.  suggest that different breeds of dogs differ in the extent to which chasing behaviour is motivated, efficacy of this type of training, and the level / number of applications of an aversive stimulus to modify behaviour. Here, breed type did not vary between groups, nor with owner reported success between groups. In the previous research relatively small numbers of animals were used, and of types unrepresented in this survey, making comparison difficult. The dogs selected for testing by Christiansen et al.  may not necessarily be representative of breed types reported here. Hence, whilst data here suggest that breed is not a strong factor in the choice of training method used for chasing or recall problems, further research is needed to investigate potential breed differences in response to different training methods.
Christiansen et al. () also suggest that the number of stimuli given to individual dogs related to a factor derived from tests considered to be related to ‘predatory motivation’. Specific behavioural characteristics such as predatory drive were not measured in this study, although owner reports of the number, occurrence of described undesired behaviours, and whether these were regarded as a ‘problem’ were measured and did not differ between groups.
No difference in age of dogs was found between groups in this study, although it has been reported that more coercive training techniques are used in older search and rescue dogs . Differences between study findings may also reflect geographical differences.
Proportion of total variance explained by model
It is salient that only between 8.4 and 10.1% of the variance between training methods used for recall or chasing problems is explained by the variables measured in this study. Hence, approximately 90% of the difference between categories is due to other factors, not measured here. It is possible that differences are explained by attitudinal factors in owners, their previous experience of different training methods, differences in relative ability to effectively apply and time interventions, and / or specific information or advice received from others, although further research is needed to investigate these factors further. In addition, the severity of the recall / chasing behaviour may have varied between groups. Although owners were asked if they considered the behaviour a ‘problem’, this is subjective, and not necessarily indicative of severity. Indeed, most owners with recall / chasing problems considered this to be ‘problematic’, presumably because behaviour of this type causes interruption of their daily routine, irritation or embarrassment.
Owner reported success of training techniques for recall / chasing problems
A higher proportion of owners who had used reward based methods for recall / chasing problems reported success with their training. Although this may reflect increased efficacy when trainers use reward based methods, there are potential confounding effects in this comparison. For example, the relative training abilities of owners may differ with type of training method, there may be different perceptions of ‘success’ between different groups, or there may be differences in the initial severity of the problem for which different types of training method are selected which could affect outcomes. There is mixed evidence for relative efficacy from previous studies, although there is overall support for the conclusion that efficacy of electronic training devices is no greater than use of other methods.
In a population of owners attending a clinical behaviour service, owners reported the types of training techniques previously used and their perceived success . A higher proportion of owners using reward based methods judged these to have had ‘positive effect’ and fewer ‘negative effect’ than those using more coercive methods. However, relatively few owners had used bark or remote activated e-collars. Eleven owners reported the use of such devices as having a positive effect, 6 a ‘negative effect’ and 6 ‘no effect’, although it is unclear for which behaviours these were used for, and the extent to which these behaviours were comparable to the use of other training techniques. In an observational study, Jones  investigated the use of e-collars to train dogs to stop attacking kiwis in a wildlife preservation programme. Thirteen dogs from a local pound underwent training, with the use of a stimulus as they approached a kiwi. However, on subsequent testing in a different context only one dog avoided approaching the kiwi.
Christiansen et al.  found a reduced likelihood of attacking sheep in a pen environment in which training with an e-collar had taken place the previous year (only 1 of 13 dogs which needed an intervention the previous year needed further training). However, no difference was found between dogs which had been given a stimulus and those which had not in a subsequent ‘path’ test, where dogs were presented unexpectedly with a lone sheep in a different context. Owners of all dogs in this study reported a reduced inclination to chase sheep, this was not influenced by whether they had received an electrical stimulus or not the previous year. According to owner report, only 1 of the 13 dogs given an electric stimulus a year previously had reduced or no interest in sheep, the rest reported as having no change. These findings may indicate that effects of e-collar training are not necessarily generalised: in other words the dog may respond as trained when in the specific context in which training has taken place, but retain the chasing behaviour in other situations.
In comparing the use of electronic bark collars with those using a citronella spray Juarbe Diaz and Houpt  reported that owners found the latter to have greater success at reducing unwanted barking. In addition, owner perception was that the e-collars were less humane to use on their dogs, although this may have had an impact on their evaluation of efficacy.
Christiansen et al.  found that dogs which had never seen sheep before had an increased chance of attacking sheep in a confrontation test compared to those which had experienced sheep – this may suggest that more dogs which chase sheep are those that are naïve to sheep rather than being established chasers. Apart from highlighting the importance of preventing such behaviour through careful introduction of puppies to livestock, dogs which chase through novelty / excitement may have their behaviour modified more easily than those with well-established chase responses. Nevertheless, apparently regardless of the extent to which the response is established, CABTSG  suggest that other training methods can be successfully used in those situations where e-collars are purported to be of greatest value (e.g. livestock chasing) and that successful resolution is regularly achieved by qualified individuals.
Some literature also compares the perception of owners more widely regarding the relative success of reward based and more coercive methods of training. For example, Loftus et al.  reported that across a range of undesired behaviours, owners reported reward based training as ‘more successful’ than other methods. Bussey  conducted an investigation of methods used in obedience training at a time when use of reward based training approaches were relatively new in this discipline. She suggested that dogs were no less successful where owners used reward based training rather than more traditional techniques, and that use of a fixed collar rather than choke / check chain had a positive influence on success.