Data Extraction:
Two independent reviewers extracted data onto 3 different forms;
abstract of relevant data, assess risk of bias, statistical Data.
For the abstract of relevant Data form, extracted data included year of
publication, study design, patient entry period, number of patients,
population demographics (i.e. age, sex), surgical characteristics (type
of cryoablation), drug characteristic (dosage, period and type of AAD),
place of intervention and follow up period.
For the assess risk of bias form, we worked according to the Cochrane
Collaboration’s tool for assessing risk of bias (Higgins 2011), and
extracted data relevant to each risk of bias: (16)
- Random sequence generation (selection bias)
- Allocation concealment (selection bias).
- Blinding of participants and personnel (performance bias).
- Blinding of outcome assessment (detection bias).
- Incomplete outcome data (attrition bias).
- Selective reporting (reporting bias).
- Other sources of bias.
Afterwards, we evaluated each risk as high, low, or unclear, as stated
by Higgins 2011. Discrepancies were resolved by discussing every risk of
bias until consensus was reached. Since our study has a surgical
component, blinding was not possible for ethical and practical reasons.
Furthermore, our measurement of outcome should not be affected by
unblended participants, since they are all objectively measured, for
example; morbidity and mortality.
For the statistical data we extracted, the total number of participants
in each leg of each study, % of follow up, number of serious adverse
events, number of serious adverse events related to trial, recurrence
Atrial Fibrillation, Atrial Tachycardia, Atrial Flutter all the data was
reported within 1 year of follow up post treatment.