Q:
Can you offer more information on the sampling of sensor data in the ADIS16448?
A:
The gyroscopes, accelerometers, and temperature sensors are all sampled through a common ADC channel, which uses the following sequence to collect data samples. This particular diagram illustrates the sampling sequence for one main data cycle. This diagram represents the case when the ADIS16448 is using its internal clock to control the sample rate. When using an external clock, the sequencing remains the same, but the data cycle period is compressed from 1.22ms to 0.1ms. 
Within a single cycle, the internal processor collects four samples of each gyroscope (x, y, z) and two samples of each accelerometer (x, y, z). The data "output" from this process represents the average of these multiple samples. The area with pink highlights represents the "average" sample time for each of these sensors.
The magnetometer data (x, y, z) comes from a separate ADC channel. The internal processor collects data from these sensors at 1/16th of the rate of the main data loop. This sampling process takes place right after the completion of accelerometer sampling (after second Z-ACCL cycle, which #16 in the figure above this text).
I hope that this helps and look forward to your comments, recognition and ideas for improving this content.