Variables | Model 1: Full Model | Model 2: Discussed Transplant | Model 3: Requested a Donation |

Structural variables, β (SEM), P value | |||

Edges | −8.57 (1.88), <0.001 | −7.80 (1.79), <0.001 | −7.99 (1.88), <0.001 |

GWDegree (0.25) | −0.75 (0.34), 0.03 | −0.91 (0.33), 0.006 | −0.90 (0.34), 0.007 |

GWESP (0.55) | 0.80 (0.18), <0.001 | 0.78 (0.18), <0.001 | 0.77 (0.18), <0.001 |

Dialysis clinic variables, β (SEM), P value | |||

TTS (sociality) | 0.37 (0.18), 0.04 | 0.41 (0.18), 0.02 | 0.33 (0.18), 0.06 |

TTS (homophily) | 3.42 (0.99), <0.001 | 3.42 (0.99), <0.001 | 3.25 (1.02), <0.001 |

Average seating distance (per seat; Euclidean) | −0.30 (0.10), 0.002 | −0.28 (0.10), 0.003 | −0.30 (0.10), 0.003 |

Patient attributes, β (SEM), P value | |||

Age | |||

Yr (sociality) | 0.01 (0.01), 0.19 | 0.01 (0.01), 0.24 | 0.01 (0.01), 0.17 |

Yr (homophily) | −0.01 (0.01), 0.42 | −0.01 (0.01), 0.31 | −0.01 (0.01), 0.49 |

Sex | |||

Female sex (sociality) | −0.34 (0.32), 0.29 | −0.29 (0.31), 0.34 | −0.29 (0.31), 0.34 |

Sex (homophily) | 0.14 (0.27), 0.72 | 0.17 (0.38), 0.66 | 0.17 (0.40), 0.68 |

Race | |||

White (sociality) | REF | REF | REF |

White (homophily) | −0.37 (1.18), 0.75 | −0.46 (1.18), 0.70 | −0.40 (1.16), 0.73 |

Black (sociality) | 0.22 (0.49), 0.64 | 0.11 (0.48), 0.82 | 0.22 (0.48), 0.64 |

Black (homophily) | 0.37 (0.69), 0.60 | 0.34 (0.68), 0.62 | 0.32 (0.68), 0.64 |

Hispanic (sociality) | −0.93 (0.46), 0.04 | −0.96 (0.46), 0.04 | −0.93 (0.46), 0.04 |

Hispanic (homophily) | 2.31 (0.69), <0.001 | 2.31 (0.66), <0.001 | 2.19 (0.68), 0.001 |

Multiethnic (sociality) | 1.21 (0.53), 0.02 | 0.97 (0.52), 0.06 | 1.45 (0.52), 0.03 |

Multiethnic (homophily) | −0.21 (1.33), 0.87 | 0.01 (1.38), 0.99 | −0.43 (1.34), 0.75 |

Transplant attributes, β (SEM), P value | |||

Discussed transplant with other patients (sociality) | 0.23 (0.29), 0.41 | 0.41 (0.24), 0.08 | |

Discussed transplant with other patients (homophily) | 0.66 (0.35), 0.06 | 0.64 (0.31), 0.04 | |

Requested a donation (sociality) | 0.49 (0.26), 0.06 | 0.49 (0.24), 0.04 | |

Requested a donation (homophily) | −0.23 (0.34), 0.50 | −0.03 (0.34), 0.93 | |

Model factors | |||

Null deviance | 14,187 (df, 10,234) | 14,187 (df, 10,234) | 14,187 (df, 10,234) |

Residual deviance | 474 (df, 10,213) | 479 (df, 10,215) | 478 (df, 10,215) |

AIC, BIC | 517, 669 | 517, 654 | 516, 653 |

This is the STERGM of the variables that are associated with the formation of the hemodialysis-clinic social network. We report the

*β*coefficients, which are the log odds of the formation of link; the SEM of the coefficients; and the*P*values. Edges represent the log odds of a participant forming a link with another participant, independent of the other variables, and represent the intercept of the model. GWDegree is the log odds of a participant with fewer links (*i.e*., lower degree) to form a new link compared with those participants with links (*i.e*., higher degree). GWESPs are the log odds that participants are more likely to link if they already share a link in common with another participant. These effects geometrically diminish as the number of shared links decrease. Sociality represents the propensity of a participant forming a link with any other participant. Homophily represents the propensity of a participant to form a link with another participant with the same attribute. STERGM, separable temporal exponential random graph model; GWDegree, geometrically weighted degree; GWESP, geometrically weighted edgewise shared partner; TTS, Tuesday, Thursday, and Saturday dialysis shift; REF, reference; df, degrees of freedom; AIC, Akaike information criterion; BIC, Bayesian information criterion.