Randomization Methodology
In this study, simple randomization was used to allocate participants into two intervention groups: Gong Mobilization and Mulligan Mobilization. Simple randomization ensures that each participant has an equal chance of being assigned to either group, reducing selection bias.
Unit of Randomization
The individual was used as the unit of randomization. Each participant was independently randomized into one of the two intervention groups, ensuring that treatment allocation was not influenced by external factors such as therapist preference or participant characteristics.
Randomization Strata in Stratified Randomization
Stratification was not used in this study. However, in future studies, stratified randomization could be applied to ensure balance among important variables such as age, gender, and severity of adhesive capsulitis.
Tools Used for Randomization
The randomization process was conducted using the sealed envelope method, a widely accepted technique for ensuring allocation concealment. A total of 30 sealed envelopes were prepared, with 15 assigned to the Gong Mobilization group and 15 to the Mulligan Mobilization group. Each envelope contained a card labeled with one of the two interventions. The envelopes were identical in appearance, shuffled, and drawn by participants to determine their group assignment.
Construction of the Random Sequence
A computer-generated random sequence was used to determine the group assignments before placing them into the sealed envelopes. The sequence was generated using Microsoft Excel’s RAND function to ensure an unbiased allocation process. The sequence was then printed and enclosed in the sealed envelopes to maintain allocation concealment.
Allocation Concealment
Allocation concealment was ensured in this study to prevent selection bias. The sealed envelope method was used, ensuring that neither the participants nor the principal investigator knew the group assignments in advance. The envelopes were only opened after the participant provided informed consent, ensuring an unbiased allocation process.
By implementing this method of randomization, the study minimized selection bias and maintained the integrity of the intervention comparisons.
Blinding Methodology
Blinding was implemented in this study to minimize bias and improve the reliability of results. While a full double- or triple-blind design was not feasible due to the nature of physiotherapy interventions, the following groups were blinded to various extents:
1. Participants
Participants in this study were not blinded to their intervention group, as they were actively engaged in the Gong Mobilization or Mulligan Mobilization treatment sessions. Given the hands-on nature of the interventions, it was not possible to conceal the treatment they received. However, participants were not informed of the specific hypothesis regarding which intervention was expected to be more effective.
2. Principal Investigator
The principal investigator, who also supervised the study, was not blinded, as they were involved in the randomization process and oversight of treatment administration. However, to minimize bias, the principal investigator did not participate in data collection or outcome assessment.
3. Healthcare Providers (Physiotherapists Administering the Intervention)
The physiotherapists who administered the interventions were not blinded, as they needed to apply the respective mobilization techniques according to protocol. However, they were instructed to follow standardized treatment procedures and not discuss expected outcomes with participants.
4. Data Collectors
Blinding was ensured for data collectors. They were not aware of the participants' group allocation when recording data. The assessments of pain (VAS), sleep quality (PSQI), and proprioception (LP-ART) were conducted using standardized measurement tools, reducing subjective bias in data collection.
5. Outcome Assessors
The outcome assessors were blinded to group allocation. To achieve this, participants were instructed not to disclose their treatment details during assessments. Additionally, data were recorded in a way that did not indicate the intervention group, ensuring that assessors remained unbiased when analyzing the results.
6. Data Safety and Monitoring Board (DSMB)
This study did not involve a formal Data Safety and Monitoring Board (DSMB), as it was a short-term, non-pharmacological intervention with a low risk of adverse effects. However, ethical oversight was maintained by the Institutional Review Board (IRB).
7. Manuscript Writers
The individuals involved in manuscript writing were partially blinded during the initial data analysis. The dataset used for statistical analysis was coded to obscure the intervention groups, ensuring that data interpretation remained objective until final results were compiled.