Redundancy, duplication and reiteration are not desirable in technical writing. Assume your reader remembers everything previously written! 

1. You write "As mentioned before", "As previously stated", "From section X.X we know that" in a biostat paper or thesis proposal. 
   1. Continue writing. 
      1. It is okay to continue writing, because it is okay for you to write incorrectly or sub-optimally. 
      2. We all write sub-optimally.
      3. Get the words out, finish the draft. 
   2. It is permitted that your draft may be flawed. 
      1. The words on the page are just a draft and are not important. 
      2. The words on the page are not final yet. 
      3. Therefore it is okay to change the words. 
   3. It is not okay that the final version has major flaws.
      1. Bad writing will irritate your reader.
      2. Bad writing slows the reader. 
      3. Bad writing wastes the time of everyone who has to read your paper. 
      4. Fewer people will read your paper. You will have less impact. 
      5. If you are submitting a research paper to a journal, there will be serious consequences.
         1. At best, the referees will be irritated by the poor writing and make you revise it extensively. They may suggest rejecting the paper merely because of the writing. 
         2. At worst, the editor will reject the paper without even allowing referees to put their two cents in.
      6. Bad writing will be taken as a sign that
         1. You don't care about what you are writing;
         2. That you think the topic isn't important; or
         3. That you are a poor thinker.
      7. None of the previous item is true:
         1. You wouldn't be writing this if you didn't care,
         2. You wouldn't work on this topic if you didn't think it was important.
         3. You can't be that poor of a thinker, you got into graduate school for goodness sakes!
   4. Back to the business at hand. The current text is flawed. Make it better. 
   5. ​The text says the same thing in at least two places.
      1. The text is allowed to make a statement one time. The text is allowed to make a statement one time.
      2. If a statement occurs twice, there's a good chance it occurs three times. Or more. Check. 
      3. Which copy to keep? First (contact)? Second (base)? Last (supper)?​
         1. Is the statement needed at the first occurrence, or can it wait until the second? The best place to make a statement is the place where its consequences are utilized immediately which will leave hooks in the reader's memory to make recall easier. 
         2. If you leave the statement in place at the first occurrence, state it in a way the reader will recall at each spot without a restatement.
      4. ​Remove all but one copy of the statement. 
      5. Now your task is to make sure the reader will understand the text with the removal. 
         1. Repair the text in each place where you have removed duplicate text.
         2. Smooth and shorten. 
         3. Likely you will need to rearrange text, lots of text.
         4. Can the two or three locations be combined?
2. Often there are additional duplicates: text, phrases, definitions, statements.
   1. Scan through quickly for duplicates. 
   2. Identify an important phrase that you use several times. Use global search to identify every usage. At each use, does the text say the same (or similar) thing about or with it? 
   3. Go fix. 
   4. Reduce. Do not re-use. Do not re-cycle! 
3. A related writing problem is identified by the phrase "in other words". In other words signifies what we intended to write is important, but we're pretty sure the reader won't get it from the current set of words.
   1. There is fault here; the fault is in the initial phrasing.
   2. Thus we restate the point in other words, usually immediately in the next sentence.
   3. Solution: Typically the restatement is easier to follow so keep it and delete the first flawed version.
   4. Smooth your text.
   5. Have you omitted important information from the first statement? Is it really important? If yes, add it back. Tersely. But not the whole thing. 
4. Taking a break from writing if needed. 
   1. It's hard to edit immediately after writing until you've garnered some experience switching modes. 
   2. After 10 minutes of break, go back and edit to remove duplicates. 
      1. Until you are an experienced editor, going back and editing can be painful. But editing is as important as the initial writing. Even if you're not ready, go back and edit. 
      2. Get to it. 

Enjoy!