Background
Methods
Questionnaire
Patients
Characteristics | Type 1 | Type 2 | ||
---|---|---|---|---|
N (missing)
|
Mean (SD)
|
N (missing)
|
Mean (SD)
| |
Age | 198 (0) | 39 (12) | 153 (0) | 59 (10) |
Sex: Male/Female | 108/90 (0) | - | 82/71 (0) | - |
Previously on insulin: Yes/No | 198/0 (0) | - | 38/115 (0) | - |
GHb at baseline | 197 (1) | 7.66 (1.13) | 149 (4) | 8.93 (1.12) |
Data analysis
Psychometric analysis
Alignment of scores for comparison purposes
Categorising scores as 'at ceiling/not at ceiling' or 'at floor/not at floor'
ANOVA: comparing treatment differences shown by the two questionnaires in subgroups scoring at ceiling (floor)/not at ceiling (floor)
Effect sizes: comparing the two questionnaires in subgroups scoring at ceiling (floor)/not at ceiling (floor)
Results
Psychometric analyses
Item | English (n = 83) | German (n = 250) | ||
---|---|---|---|---|
Component 1 (Satisfaction)
|
Component 2 (PercBGC)
|
Component 1 (Satisfaction)
|
Component 2 (PercBGC)
| |
1 Satisfied |
0.817
| -0.075 |
0.878
| -0.215 |
2 Hyperglycaemia | -0.029 |
0.807
| -0.272 |
0.735
|
3 Hypoglycaemia | -0.094 |
0.734
| -0.103 |
0.857
|
4 Convenient |
0.943
| -0.149 |
0.868
| -0.152 |
5 Flexible |
0.830
| 0.076 |
0.896
| -0.209 |
6 Understanding |
0.808
| -0.053 |
0.705
| -0.249 |
7 Recommend |
0.812
| -0.139 |
0.865
| -0.190 |
8 Continue |
0.915
| -0.099 |
0.899
| -0.159 |
Item | Component 1 Satisfaction | Component 2 Perceived Hyperglycaemia | Component 3 Perceived Hypoglycaemia |
---|---|---|---|
1 Satisfied |
0.812
| -0.095 | -0.221 |
2 Hyperglycaemia | -0.043 |
0.968
| 0.120 |
3 Hypoglycaemia | -0.080 | 0.120 |
0.976
|
4 Convenient |
0.944
| -0.111 | -0.099 |
5 Flexible |
0.828
| 0.124 | -0.025 |
6 Understanding |
0.808
| -0.025 | -0.051 |
7 Recommend |
0.818
| -0.266 | 0.095 |
8 Continue |
0.916
| -0.098 | -0.037 |
Item | Component 1 Satisfaction | Component 2 Perceived Hyperglycaemia | Component 3 Perceived Hypoglycaemia |
---|---|---|---|
1 Satisfied |
0.858
| -0.320 | -0.019 |
2 Hyperglycaemia | -0.213 |
0.940
| 0.192 |
3 Hypoglycaemia | -0.150 | 0.175 |
0.955
|
4 Convenient |
0.883
| -0.009 | -0.185 |
5 Flexible |
0.906
| -0.088 | -0.195 |
6 Understanding |
0.717
| -0.093 | -0.242 |
7 Recommend |
0.854
| -0.240 | -0.050 |
8 Continue |
0.884
| -0.247 | -0.005 |
Distributions of scores
ANOVA: comparing treatment differences shown by the two questionnaires in subgroups scoring at ceiling (floor)/not at ceiling (floor)
Main Effects & Interactions | Type 1 Study | Type 2 Study | ||||
---|---|---|---|---|---|---|
F
|
df1, df2
|
p
|
F
|
df1, df2
|
p
| |
Treatment |
15.71
|
1,181
|
<0.0001
| 0.85 | 1,125 | 0.360 |
Ceiling | 0.17 | 1,181 | 0.678 | 2.61 | 1,125 | 0.109* |
Questionnaire |
538.04
|
1,181
|
<0.0001
|
1833.88
|
1,125
|
<0.0001
|
Treatment × Ceiling | 0.80 | 1,181 | 0.373 | 0.04 | 1,125 | 0.840 |
Treatment × Questionnaire |
11.70
|
1,181
|
0.001
| 1.81 | 1,125 | 0.181 |
Ceiling × Questionnaire |
30.44
|
1,181
|
<0.0001
|
62.37
|
1,125
|
<0.0001
|
Treatment × Ceiling × Questionnaire | 0.00 | 1,181 | 0.948 | 3.18 | 1,125 | 0.077 |
Change Questionnaire | Status Questionnaire | |||||||
---|---|---|---|---|---|---|---|---|
glargine treatment
|
NPH treatment
|
glargine treatment
|
NPH treatment
| |||||
At Ceiling
|
Not Ceiling
|
At Ceiling
|
Not Ceiling
|
At Ceiling
|
Not Ceiling
|
At Ceiling
|
Not Ceiling
| |
Type 1 Study
| ||||||||
Mean change | 12.709 | 10.744 | 9.278 | 6.196 | -0.427 | 2.163 | -1.014 | 0.353 |
SD | 7.023 | 4.885 | 6.679 | 7.707 | 2.629 | 3.078 | 2.425 | 3.235 |
N
|
55
|
43
|
36
|
51
|
55
|
43
|
36
|
51
|
Type 2 Study
| ||||||||
Mean change | 16.273 | 14.115 | 15.806 | 14.565 | 4.269 | 0.432 | 2.783 | 0.236 |
SD | 3.330 | 3.963 | 3.345 | 3.776 | 1.655 | 3.465 | 1.290 | 3.599 |
N
|
44
|
26
|
36
|
23
|
44
|
26
|
36
|
23
|
Main Effects & Interactions | Type 1 Study | Type 2 Study | ||||
---|---|---|---|---|---|---|
F
|
df1, df2
|
p
|
F
|
df1, df2
|
p
| |
Treatment |
6.86
|
1,188
|
0.010
| 0.03 | 1,139 | 0.957 |
Floor |
8.00
|
1,188
|
0.005
|
7.45
|
1,139
|
0.007
|
Questionnaire |
32.63
|
1,188
|
<0.0001
|
11.88
|
1,139
|
0.001
|
Treatment × Floor |
4.80
|
1,188
|
0.030
| 3.08 | 1,139 | 0.081 |
Treatment × Questionnaire |
5.79
|
1,188
|
0.017
†
| 1.46 | 1,139 | 0.229 |
Floor × Questionnaire |
65.24
|
1,188
|
<0.0001
|
23.69
|
1,139
|
<0.0001
|
Treatment × Floor × Questionnaire | 1.36 | 1,188 | 0.245 |
6.19
|
1,139
|
0.014
|
Change Questionnaire | Status Questionnaire | |||||||
---|---|---|---|---|---|---|---|---|
glargine treatment
|
NPH treatment
|
glargine treatment
|
NPH treatment
| |||||
At Floor
|
Not Floor
|
At Floor
|
Not Floor
|
At Floor
|
Not Floor
|
At Floor
|
Not Floor
| |
Type 1 Study
| ||||||||
Mean change | -0.755 | -0.980 | -0.581 | -0.041 | 0.429 | -0.578 | 0.360 | -0.337 |
SD | 1.422 | 1.378 | 1.277 | 1.471 | 0.520 | 0.586 | 0.630 | 0.860 |
N
|
49
|
51
|
43
|
49
|
49
|
51
|
43
|
49
|
Type 2 Study
| ||||||||
Mean change | -0.842 | -1.350 | -1.393 | -0.300 | 0.395 | -0.950 | 0.295 | -1.200 |
SD | 1.645 | 1.599 | 1.510 | 1.947 | 0.854 | 0.742 | 0.666 | 0.823 |
N |
57
|
20
|
56
|
10
|
57
|
20
|
56
|
10
|
Main Effects & Interactions | Type 1 Study | Type 2 Study | ||||
---|---|---|---|---|---|---|
F
|
df1, df2
|
p
|
F
|
df1, df2
|
p
| |
Treatment | 0.89 | 1,185 | 0.346 | 0.04 | 1,137 | 0.841 |
Floor | 1.01 | 1,185 | 0.315 | 1.51 | 1,137 | 0.221 |
Questionnaire |
28.72
|
1,185
|
<0.0001
|
8.88
|
1,137
|
0.003
|
Treatment × Floor | 3.46 | 1,185 | 0.064 | 1.19 | 1,137 | 0.278 |
Treatment × Questionnaire | 0.34 | 1,185 | 0.558 | 0.02 | 1,137 | 0.901 |
Floor × Questionnaire |
35.08
|
1,185
|
<0.0001
|
37.55
|
1,137
|
<0.0001
|
Treatment × Floor × Questionnaire |
3.93
|
1,185
|
0.049
‡
| 0.94 | 1,137 | 0.335 |
Change Questionnaire | Status Questionnaire | |||||||
---|---|---|---|---|---|---|---|---|
glargine treatment
|
NPH treatment
|
glargine treatment
|
NPH treatment
| |||||
At Floor
|
Not Floor
|
At Floor
|
Not Floor
|
At Floor
|
Not Floor
|
At Floor
|
Not Floor
| |
Type 1 Study
| ||||||||
Mean change | -1.208 | -0.767 | -1.600 | 0.171 | 0.313 | -0.459 | 0.350 | -0.311 |
SD | 1.414 | 1.603 | 1.430 | 1.530 | 0.673 | 0.798 | 0.669 | 0.706 |
N
|
24
|
73
|
10
|
82
|
24
|
73
|
10
|
82
|
Type 2 Study
| ||||||||
Mean change | -0.933 | -0.644 | -1.462 | -0.185 | 0.600 | -1.025 | 0.385 | -0.972 |
SD | 1.831 | 2.057 | 2.184 | 2.066 | 0.967 | 1.112 | 0.961 | 0.949 |
N
|
15
|
59
|
13
|
54
|
15
|
59
|
13
|
54
|
Change in treatment satisfaction
Type 1 trial
Type 2 trial
Change in perceived hypoglycaemia
Type 1 trial
Type 2 trial
Change in perceived hyperglycaemia
Type 1 trial
Type 2 trial
Effect sizes: comparing the responsiveness to treatment differences of the two questionnaires in subgroups scoring at ceiling (floor)/not at ceiling (floor)
Study | At Ceiling (("AC")/ At Floor ("AF") | t (df) | D (= Z of difference between t for DTSQc and t for DTSQsDiff) | Z of difference between D in the AC/Not AC groups or in the AF/Not AF groups | |
---|---|---|---|---|---|
DTSQc Questionnaire
|
DTSQsDiff Questionnaire
| ||||
Treatment Satisfaction
| |||||
Type 1 | AC | 15.64 (95) | -2.44 (91) | 10.15 | 3.83**** |
Not AC | 11.97 (97) | 3.30 (94) | 4.73 | ||
Type 2 | AC | 27.10 (89) | 0.39 (83) | 11.23 | 4.05**** |
Not AC | 26.81 (52) | 7.37 (50) | 5.51 | ||
Perceived Hypoglycaemia
| |||||
Type 1 | AF | -4.73 (95) | 6.65 (91) | -7.54 | -6.71**** |
Not AF | -3.48 (99) | -6.62 (100) | 1.94 | ||
Type 2 | AF | -7.37 (114) | 4.79 (113) | -8.07 | -7.47**** |
Not AF | -2.70 (32) | -7.40 (29) | 2.49 | ||
Perceived Hyperglycaemia
| |||||
Type 1 | AF | -5.48 (33) | 2.85 (33) | -5.22 | -5.73**** |
Not AF | -2.14 (159) | -6.45 (156) | 2.88 | ||
Type 2 | AF | -3.15 (27) | 2.77 (28) | -3.84 | -4.08**** |
Not AF | -2.27 (113) | -10.32 (116) | 1.93 |