Well, it appears my suspicions were correct. I do seem to have quite a low cadence and it doesn't seem to matter if I am doing a tempo 5k or a long slow run. 158 steps per minute seems to be the golden number! I am going to try C25K+ Stamina again tomorrow and see if I can stick to 160 for a decent length of time.
Is there anything I can do to up the cadence a bit? Other than just "move my legs faster" which just knackers me out very quickly.
Try shortening your stride.
I agree with Bazza1234 . shorten your stride; having said that, I find it difficult. I appear, I am sure to an onlooker, as if I am doing an odd dance, when I try to alter my pace!
Have you used Speed much? I found that quite useful...also, and don't laugh, using music and changing pace with the beat, ( ABBA) was the favourite) helped too. There was one of my rambling posts on this and one or two folk have been having a bit of fun with it. It is quite challenging and really focuses you.. just a thought.
I am speedier now. I know this because, even if I am not monitoring my pace, I am covering a lot more distance, in a shorter time, ( obvious eh?) and usually ending up too far from home and having to run back quickly! 
Concentrate on picking your heels up behind you as you shorten your stride. Try it when walking first.
Thanks... I definitely need something to focus on. I am trying to lean forward more and plant my foot in the middle rather than on my heel so I think focussing on shortening my stride by picking up my heels may just help both of those.
Do be careful if you're changing where you land on your foot. I did this by experimenting a bit on one run, and then the next time I went out, I ran a whole 5km not landing on my heel. The next day I could barely walk and stairs were almost impossible, my calf muscles were so tight!
Once I was mobile and running again, I did a C25K type of run for a bit in the old way, switch for a bit, then switch back and repeat. This was rather more successful!
In terms of increasing your cadence, the leader of my abs class makes us do the occasional "running on the spot" for 30 seconds - but this is no light shifting your weight from one foot to the other, he insists on "high knees" and then makes us go faster and faster. Could be worth it every now and then when you are warmed up, just so your legs feel what it's like to move faster. Just an idea.
All good advice here. All I'd add is a caution. Increase your cadence slowly (like everything else in running!) and gradually. Rather than run at 160 for the whole run try intervals where you're running at your normal cadence for a while, then back to 160. This eases your body into the change as it does take a lot out of you!
I'm another with slow cadence. Doing Stamina and Speed is a great idea as I've found they have increased my cadence over time. I'd also suggest doing lots of interval work, it really does speed you up.
Cadence testing 
Cadence at last! Mixed results. 
Pace/cadence/speed/stride length ... someone please help me
C25k+ I'm not sure if it will work for me...
Anyone got a plan
