Organising by theme

The easiest way to move from a list of summaries to a real review is to organise by theme, not by paper.

Find your themes

Go back to your literature matrix. Look down each column for groups:

• papers that use the same approach (all use data augmentation)
• papers that ask the same sub-question (all study accents)
• papers that disagree about something
• changes over time (older methods vs newer methods)

Each group becomes a section or paragraph of your review.

Write each paragraph around a point

A strong review paragraph has a clear shape:

1. Topic sentence: the point you are making. "Data augmentation helps most when real training data is very scarce."
2. Evidence: what several studies found, compared with each other. "With under 10 hours of speech, augmentation cut errors by a quarter (A, 2022; C, 2024), while with 50 hours the gain was small (B, 2023)."
3. Your view: what it means, and its limits. "However, all three studies used read speech, so the effect on conversation is unknown."

Useful phrases for comparing

• "Several studies agree that..."
• "In contrast, X found..."
• "One explanation for this difference is..."
• "These results are limited by..."
• "No study so far has tested..."

Order your themes

Go from broad to narrow, ending with the theme closest to your own question. Then the gap you describe next follows naturally.

RememberIf a paragraph cites only one paper, ask whether it is a real theme or just a summary in disguise.