Table 5 Summary of key sections across the CGI-C training document and final item/instruction document and associated CE/CD data

Title and purpose of CGI-C instruction document

✓

✓

N/A: title and purpose based on existing CGI-C principles [15]

Assessed understanding of the title, instructions and the relevance of a Duchenne-specific CGI-C

All clinicians (9/9) understood the title and 8/9 understood the purpose of the CGI-C

All clinicians (9/9) considered the content relevant

All clinicians (9/9) reported that the inclusion of information in the training document relating to how the CGI-C instructions had been developed (i.e. involving individuals, caregivers and neurologists) was informative and supported its credibility

Duchenne CGI-C definition and CGI-C items and response options

✓

✓

N/A: definition based on existing CGI-C principles [15]

N/A: definition based on existing CGI-C principles [15]

All clinicians (9/9) understood the Duchenne CGI-C definition and 7/8 considered the focus on symptoms and functional ability as relevant to the assessment of ‘overall health’

Several clinicians (4/9) advocated the use of the phrase ‘clinical status’ to represent symptoms and functional ability over the phrase ‘overall health’ as the latter was considered too broad

The majority of clinicians asked (5/7) understood the Duchenne CGI-C item wording and 4/5 asked thought it was easy to complete

Information to consider when completing the CGI-C

✓

✓

Symptoms, physical functioning and ability to perform ADL were the key themes that arose as core to Duchenne in the CE clinician data

10 symptoms raised (muscle weakness, fatigue cardiac symptoms, enlarged calves, respiratory problems, muscle stiffness/tightness, contractures, pain, scoliosis and gastro-intestinal issues)

15 physical functioning activities raised (standing still, standing on heels, standing on one leg, standing up from a chair, standing up from lying on the floor, standing up from sitting on the floor, lifting head, walking, stepping onto box, stepping off of box, hopping, jumping, running, climbing stairs, difficulties with upper limb functioning)

Five ADL difficulties were raised (bathing/showering, toileting, dressing, brushing hair, brushing teeth)

Assessed understanding of the instructions

The majority of clinicians (7/8) understood the ‘information to consider’ section

Several of the clinicians asked (4/8) reported that they would improve the clarity of the ‘symptom’ domain in the ‘information to consider’ section by including key symptoms in addition to muscle weakness. The symptoms pain and fatigue were added to this section.

CGI-C determining change in response category descriptions

✓

✓

Descriptions of change category information was informed by the CE data where there was a focus on any change being meaningful

Meaningful improvement and worsening focused on symptoms and functional ability;a key theme was that any loss or gain of independence that led to changes in the need or level of assistance was important. In addition, the following themes emerged:

Change in level of effort and confidence when carrying our activities

Changes in speed, endurance and quality of movements

Assessed understanding of the instructions and item including descriptions

The majority of clinicians asked understood the descriptions of each level of change: ‘very much worse’ (9/9), ‘much worse’ (8/9), ‘minimally worse’ (9/9), ‘no change’ (8/8), ‘minimally improved’ (8/8), ‘much improved’ (7/7), ‘very much improved’ (6/6)

CGI-C determining change response category example

✓

✗

The examples were based on the themes raised by clinicians in the CE interviews and focused on symptoms such as muscle weakness, pain and physical functioning, as well as the amount of assistance or time required to complete a task

Assessed understanding of the instructions, domains and the relevance of the level of change descriptions and examples

The majority of clinicians asked considered the descriptions of each level of change to be relevant: ‘very much worse’ (8/9), ‘much worse’ (9/9), ‘minimally worse’ (5/5), ‘no change’ (7/8), ‘minimally improved’ (5/5), ‘much improved’ (5/5), ‘very much improved (4/5)

All of the clinicians asked understood the examples of each level of change: ‘very much

worse’ (9/9), ‘much worse’ (9/9), ‘minimally worse’ (9/9), ‘no change’ (6/6), ‘minimally improved’ (8/8), ‘much improved’ (6/6), ‘very much improved’ (5/5)

The majority of clinicians asked consider the examples for each level of change to be relevant: ‘very much worse’ (8/9), ‘much worse’ (9/9), ‘minimally worse’ (8/9), ‘no change’ (7/8), ‘minimally improved’ (5/5), ‘much improved’ (8/8), ‘very much improved’ (4/5)

Example of CGI-C score vignettes

✓

✗

The vignettes were informed by the CE data. Changes in standing up from sitting and walking and the associated consequences in daily life of improving or worsening on these functions, informed the creation of the vignettes

Standing up from sitting on the floor and walking were of key importance clinically and thus chosen for the vignettes (see Additional file 1)

Assessed understanding of the vignettes

The majority of clinicians asked (6/7) thought the vignettes were useful, agreed with the assigned level of change rating (3/5) and considered the treatment notes relevant to Duchenne (2/2)