Schema for Multicentre Trials
Use We use a study ID consisting of 3 components in the format XXXXXX.XXXX:
Study IDs are stored as character values to ensure that zero place holders are not dropped. The randomisation number is assigned sequentially at each site after randomisation. A decimal point is placed between the site code and randomisation number. This allows sites to monitor their own recruitment and ensures the ID can be easily converted to a numerical value if manipulations are required. The study number ensures that samples can that samples and data can be identified across studies.The following site codes have been Site codes are based on those used in previous Australasian multicentre trials and have been retained for continuity:
Auckland City Hospital
Hawke’s Bay Hospital
North Shore Hospital
Tauranga Hospital (Bay of Plenty)
Randomisation in multiple pregnancy
To deal with unit of analysis issues, there are two common solutions:
- Add a suffix where 0 is mother; infants are coded 1, 2 and 3 according to birth order in multiple pregnancy or 5 for singleton. A surviving twin would be coded as 1.
- Assign a separate "randomisation number" to the fetuses, e.g., start mothers at 1000 and babies at 5000.
For perinatal studies, we recommend the following numbering:
- Mother first pregnancy in study XXXXXX.0001 to XXXXXX.2999
- Mother second pregnancy in study XXXXXXX.9001 to XXXXXX.9999
- Singleton fetus/neonate XXXXXX.3001 to XXXXXX.5999
- First twin or triplet XXXXXX.6001 to XXXXXX.6999
- Second twin or triplet XXXXXX.7001 to XXXXXX.7999
- Third triplet XXXXXX.8001 to XXXXXX.8999
Click here for the complete list of LifePath study and site codes.