Table 1 Definition and formula for diversity of contacts

Heterogeneity indicates, per healthcare professional; i, the degree of the number of relationships outside their own discipline in relation to the number of all possible different disciplines with which they are in contact. The number of times healthcare professional; i, has been chosen by the other healthcare professionals is considered (in-degree), because this parameter has a higher reliability with reality than the relationships indicated by the healthcare professional themselves (out-degree). Diversity is thus determined on the basis of two components: P_iR, the proportion of healthcare professions i’s relationships with members of other disciplines, R_divi, regarding all relationships of healthcare professions i R_i; and D_iD, the number of diverse disciplines with which healthcare professions; i, has contact outside of his own discipline, D_divi, regarding all disciplines within the network minus the own discipline of healthcare professions, i D_i:

P_iR = (R_i − R_divi)/R_i

D_iD = D_divi/D_i

For every healthcare professional within the network, diversity is defined as:

H_i = ΣP_iR × D_iD

When a healthcare professional has relationships within all professionals, and as many professionals speak outside their own professionals as within their own professional, then P_iR = 0.5 and D_iD = 1. The diversity of relationships for this healthcare professional, H_i, is 0.5/1 = 0.5. The score for diversity in relationships can vary between 0 and 1.