When ED staff require help to solve work-related problems they ask colleagues from within their own profession, as indicated by the colour and shape of nodes in Figure 1. Most participants are positioned adjacent to those from their own profession. Most nurses are located in the centre and right-hand side of the network, most doctors in the left side of the network, the allied health professionals are located throughout the network and most administrative staff are positioned in the top right quarter of the network. Those in the centre of the network ask more people or are asked by more people for help to solve a work-related problem. They are more active in working with others to find solutions than those on the periphery.

Staff with a range of experiences are located throughout most of the problem-solving network as indicated by the range of sizes of the nodes throughout the network in Figure 1. However, many of the junior doctors are located in close proximity to each other, peripherally, on the left of the network. Less experienced medical staff seem thus to rely on each other rather than ask more senior staff for help to solve work-related problems.

This network is relatively highly connected with 53% of all possible ties represented (Connectedness = 53%, Table 1), namely given all the possible ties between individuals, 53% of these are reported for the work-related problem solving network. There are more ties within some of the professional groups than overall, with 69% of ties present between nurses. Only 45% of ties are represented between doctors. There are only 17% of ties present between allied health professionals, who instead tend to seek help from nurses and doctors.

With 43% of ties reciprocated (Reciprocity = 43%, Table 1), ie both parties agreed that they sought help from each other, there are horizontal as well as hierarchical aspects to the structure of the network. Although there are particular individuals being asked for help by other members in the unit, assistance is also given and received amongst many of the staff. The senior doctors and senior nurses provide help to a large number of the ED staff. Senior doctor 4 has the greatest number of staff members asking him or her for help to solve work-related problems, with 92 people reporting Senior doctor 4 as a source of help (in-degree = 92). Three other senior doctors and seven senior nurses also have a large number of other people asking them for advice, as indicated by their high in-degree centralities (Table 1). Senior doctor 6 is the most powerful actor, with the highest betweenness centrality value (Betweenness centrality = 280.9), indicating that they are sitting on many of the shortest routes between other members of the unit. In essence this demonstrates that much communication passes through them and that they communicate with many people. Two other senior doctors and seven senior nurses are also dominant in the network. They may be controlling information related to solving work-related problems or have the potential to do so, and have capacity to help others in solving work-related problems.

Help is readily available in this unit, shown by the high level of connectedness with an average of only one to two degrees of separation between any pair of nodes in the network, indicating that on average ED staff are either directly connected to each other or only one other person is between each pair of ED staff members (degree of separation = 1 to 2, Table 1), with no individual more than three degrees of separation from any other (maximum degree of separation = 3, Table 1). There are no isolates in this network, indicating that all ED staff members are involved in solving problems.

As in the problem-solving network, some of the senior doctors play a central role in the medication advice-seeking network. This is shown in Figure 2, where Senior doctors 1, 2 and 6, and Junior doctor 11 and Junior doctor 24 are more centrally located than their other medical colleagues, and in Table 1, where Senior doctors and Junior doctors have high in-degrees.

The medication advice-seeking network is moderately connected with 37% of all possible ED staff connections present (Density of whole network = 37%, Table 1). Sources of medication advice are readily available with each individual no more than four degrees of separation from any other (Maximum degree of separation = 4, Table 1), and they average only one to two degrees of separation from each other (Degree of separation = 1 to 2, Table 1). The ties between the nurses are the most dense (58%, Table 1). Ties between doctors are also quite dense (37%). The ties between allied health professionals are less dense (25%), as are those between administrative staff (26%). There were no isolates in this network.

Having only 26% of medication advice-seeking ties reciprocated (Reciprocity = 26%, Table 1) indicates the importance of particular individuals in the network with high in-degree centralities such as Senior doctor 1 (in-degree = 77), Senior doctor 2 (in-degree = 80), Senior doctor 5 (in-degree = 65), Senior doctor 6 (in-degree = 76) and Senior doctor 7 (in-degree = 66), Junior doctor 6 (in-degree = 63), Junior doctors 8 and 9 (in-degree = 64) and Senior nurse 2 (in-degree = 68). They are people on whom many other ED staff depend to provide advice regarding medication decisions and tasks. They seek or are sought by more individuals for medication advice, as well as by more nurses than their other medical colleagues. Junior doctor 2 is located at some distance from other doctors, indicating that he or she asks or is asked for help by more administrative staff and nurses than the other doctors.

More staff agreed (42.1%) than disagreed (34.8%) with the statement that doctors often seek advice from nurses about prescribing decisions (Table 2). Many of those who disagreed were doctors located peripherally from the centre of the medication advice network and separated from nurses. Many of these staff were junior doctors located moderately peripherally in the network, indicating that they do not interact with a lot of nurses. Most staff (67.9%) agreed that if doctors and nurses talked more frequently, there would be fewer medication errors, and only four staff disagreed (Table 2). No staff members strongly disagreed that if doctors and nurses talked more frequently, there would be fewer medication errors.

ED staff largely socialise tribally, ie with colleagues from within their own profession (Figure 3). However, Junior doctors 2, 11 and 24 are located more centrally than other doctors, and Allied health professional 4 is located more centrally and apart from other allied health professionals indicating that these individuals also socialise with those from different professions.

Individuals with a variety of experience are located throughout the socialising network in the ED. This network is sparsely connected, with only 18% of all possible ties between people present (Connectedness = 18%, Table 1). This is the lowest density of the three networks examined. The relationships within the administrative group (49%) (Table 1) and the nursing group (42%) are more dense than between all members of the socialising network, but the socialising ties between the doctors (12%) and between the allied health professionals are less dense (8%). Due to the nature of emergency shift work, breaks need to be staggered so ED doctors may find it more difficult to socialise with each other than would doctors working in other clinical areas.

Individuals with whom to socialise are not very available. Although on average each connected individual is only one to two steps away from each other individual (Degree of separation = 1 to 2, Table 1), they can be up to seven steps away (Maximum degree of separation = 7, Table 1). A very low reciprocity (24%, Table 1) of the socialising ties indicates that there was a low level of agreement between socialising pairs. There was also one isolate in the socialising network (Junior doctor 20).

Some of the staff who appear central in the socialising network are Senior RN 4, and Senior nurses 6, 11 and 15. Nurses from across a range of positions are important in the socialising network. Senior nurse 12 was reported to socialise with 42 other ED staff (in-degree = 42). Many ED staff also reported socialising with Senior nurses 4, 6 and 9, Senior RNs 4, 5 and 7, Junior RNs 1, 2, 3 and 8, and EN 4. Senior RN 4 also reported socialising with 95 other staff members from ED (out-degree = 95).

Drawing on data from one ED limits generalisability. Network analysis reveals social and professional structures and characteristics but does not disclose the tenor of the communication or interaction.

Knowledge of how professionals relate and the social and professional structures which they form can provide insights of potential benefit to ED staff, their leaders, policymakers and researchers. Training in cross-disciplinary communication and interaction may be beneficial in the ED in order to improve these characteristics.