Phase I

PHASE I – Determine the content and face validity of the vulvar acute genital injury score (VAGIS) using a modified electronic Delphi (e-Delphi) method in a national panel of SA forensic experts.

Scale Development (De Vellis, 2003)

  • Step 1 – Determine clearly what is it you want to measure – this study seeks to measure AGI after SA
  • Step 2 – Generate an item pool – the item pool will be generated through a rigorous review of literature and the investigators empirical clinical experience
  • Step 3 – Determine the format for measurement – the format for measurement will be in the form of the Vulvar Acute Genital Injury Score (VAGIS)
  • Step 4 – Have the initial item pool reviewed by experts – The investigator of the proposed study will reduce the item pool before initial review by experts. The reduced item pool will be evaluated for content validity (described later) by assessing relevance, clarity and appropriateness by an expert Delphi panel (described later).
  • Step 5 – Consider inclusion of validation items – the additional items to be validated by the expert Delphi panel will be the theoretical framework, the measurement framework, the operational definitions, scoring, format, and overall ability of the VAGIS is at measuring AGI after SA.
  • Step 6 – Administer items to a development sample – the VAGIS will be validated using content experts as described in Step 4 and Step 5.
  • Step 7 -Evaluate the items – Items on the VAGIS will be evaluated using content experts as described in Step 4 and Step 5.
  • Step 8 -Optimize scale length – The length of the VAGIS will be optimized using content experts as described in Step 4 and Step 5.


Basic assumption: A group’s opinion is more valid than an individual’s opinion. A multi-staged survey method used to quantify the judgment of experts, assess priorities, and/or to make long range forecasts on a new or subjective topic that lacks high-quality evidence.

3 types: Classic, Modified, Modified e-Delphi

Classic Delphi
Usually consists of 2-3 rounds.

Round 1 – A survey is sent for Item generation. Item reduction occurs, and themes are identified.
Round 2 – A consensus level is set. A summary of results is sent to the participants. Descriptive statistics (mean, mode, percent agreement) are employed and a free text is evaluated using a coding schema.
Round 3 – A summary of results is sent to the participants. Data are analyzed in a similar manner as Round 2. Additional rounds are performed as necessary until consensus is achieved.

Modified Delphi

Round 1 – item generation round is replaced by opening statements developed after a rigorous review of the literature.
Round 2 & 3 – Then continues as classic Delphi method until the predetermined consensus level is achieved. Consensus is usually achieved in 2 rounds.

Modified e-Delphi

This is the approach for the current study. Similar to modified Delphi method. Consensus is usually achieved in 2 rounds. Uses internet online surveys such as Survey Monkey or RedCap, which allows faster turnaround time for participant responses and contains cost.


Establishing Content and Face validity – Delphi participants will be asked these seven questions in order to validate the content of each item on the scale.

  1. Does the general theoretical framework research support inclusion of the item on the tool?
  2. Does the measurement framework support how the item is measured on the VAGIS?
  3. Is the operational definition for each of the item choices correct?
  4. Are the choices for each of the item scores appropriate?
  5. Is the format appropriate?
  6. Is the level of language appropriate?
  7. Overall affirmation of this item?