Table 2.

Loss to Follow-Up, Improvement in Oral Health–Related QoL, and Self-Reported Oral Health Complaints by Intervention, Including All GP Offices in the Analysis

ExperimentalControlχ2 StatisticP ValueIntracluster Correlation CoefficientAdjusted χ2 StatisticAdjusted P Value
Study details
  No. of GP offices1212
  No. of study participants352412
Loss to follow-up
  GP offices0 (0)0 (0)N/AN/AN/AN/AN/A
  Study participants130 (36.9)91 (22.1)20.346<.0010.2142.354.125
Improvement in oral health–related QoLan = 162bn = 243b
  Functional limitation22 (13.6)24 (9.9)1.324.25–0.008c1.324.25
  Physical pain45 (27.8)53 (21.8)1.887.17–0.006c1.887.17
  Psychologic discomfort27 (16.7)26 (10.7)3.043.0810.0311.924.165
  Physical disability15 (9.3)17 (7.0)0.684.4080.0350.412.521
  Psychologic disability25 (15.4)21 (8.6)4.451.0350.0233.106.078
  Social disability7 (4.3)8 (3.3)0.289.5910.0110.240.624
  Handicap17 (10.5)12 (4.9)4.513.0340.0143.591.058
  OHIP-NL14 total score57 (35.2)63 (25.9)3.997.0460.0023.857.049
Improvement in self-reported oral health complaintsn = 222bn = 321b
  Pain in mouth33 (14.9)28 (8.7)4.965.0260.0173.451.063
  Dry mouth38 (17.1)59 (18.4)0.143.7050.0190.095.758
  Bad breath19 (8.6)19 (5.9)1.405.236–0.018c1.405.236
  Any78 (35.1)89 (27.7)3.383.0660.0361.750.186
  • GP = general practitioner; N/A = not applicable because GP office is cluster level itself; OHIP-NL14 = 14-item Oral Health Impact Profile; QoL = quality of life.

  • Note: Data in Experimental and Control columns for rows Loss to follow-up and below are presented as n (%).

  • a Subdomains according to Slade.21

  • b No. of patients with a completed baseline and follow-up questionnaire.

  • c To calculate adjusted χ2 statistics, negative intracluster correlation coefficients were set to 0 for these variables.30,31